Roman Empire

The Roman Empire was the post-Republican phase of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean. The term is used to describe the Roman state during and after the time of the first emperor, Augustus. The nearly 500-year-old Roman Republic, which preceded it, had been weakened by several civil wars. Several events are commonly proposed to mark the transition from Republic to Empire, including Julius Caesar's appointment as perpetual dictator (44 BC), the victory of Octavian at the Battle of Actium (2 September 31 BC), and the Roman Senate's granting to Octavian the honorific Augustus (4 January 27 BC).

The Latin term Imperium Romanum (Roman Empire), probably the best-known Latin expression where the word imperium denotes the sphere of human life (for example some countries - lands with people) subdued to military commander - imperator, under Roman rule. Roman expansion began in the days of the Republic, but reached its zenith under Emperor Trajan. At this territorial peak, the Roman Empire controlled approximately 6,500,000 km² of land surface. Because of the Empire's vast extent and long endurance, Roman influence upon the language, religion, architecture, philosophy, law, and government of nations around the world lasts to this day.

In the late 3rd century AD, Diocletian established the practice of dividing authority between four co-emperors, in order to better administer the vast territory. In 330 AD, the first Christian Emperor Constantine I, founded Constantinople as new capital of the Empire. In 392 AD, Emperor Theodosius appointed as co-emperors, his elder son Arcadius for the east part of the Empire and his younger son Honorius for the west part of the Empire. After the death of Theodosius in 395 AD, the empire was finally divided to its east part having Constantinople as capital, and to its west part having Mediolanum (since 402) then Ravenna as capital.

The Western Roman Empire collapsed in 476 as Romulus Augustus was forced to abdicate by Odoacer. The Eastern Roman or Byzantine Empire endured until 1453 with the death of the last de jure Roman Emperor Constantine XI and the capture of Constantinople by the Ottoman Turks led by Mehmed II.

Emperor
The powers of an emperor, (his imperium) existed, in theory at least, by virtue of his "tribunician powers" (potestas tribunicia) and his "proconsular powers" (imperium proconsulare). In theory, the tribunician powers (which were similar to those of the Plebeian Tribunes under the old republic) made the emperor's person and office sacrosanct, and gave the emperor authority over Rome's civil government, including the power to preside over and to control the Senate.

The proconsular powers (similar to those of military governors, or Proconsuls, under the old republic) gave him authority over the Roman army. He was also given powers that, under the republic, had been reserved for the Senate and the assemblies, including the right to declare war, to ratify treaties, and to negotiate with foreign leaders.

The emperor also had the authority to carry out a range of duties that had been performed by the censors, including the power to control senate membership. In addition, the emperor controlled the religious institutions, since, as emperor, he was always Pontifex Maximus and a member of each of the four major priesthoods. While these distinctions were clearly defined during the early empire, eventually they were lost, and the emperor's powers became less constitutional and more monarchical.

Realistically, the main support of an emperor's power and authority was the military. Being paid by the imperial treasury, the legionaries also swore an annual military oath of loyalty towards him, called the Sacramentum.

The death of an emperor led to a crucial period of uncertainty and crisis. In theory the senate was entitled to choose the new emperor, but most emperors chose their own successors, usually a close family member. The new emperor had to seek a swift acknowledgement of his new status and authority in order to stabilize the political landscape. No emperor could hope to survive, much less to reign, without the allegiance and loyalty of the Praetorian Guard and of the legions. To secure their loyalty, several emperors paid the donativum, a monetary reward.

Senate
While the Roman assemblies continued to meet after the founding of the empire, their powers were all transferred to the Roman Senate, and so senatorial decrees (senatus consulta) acquired the full force of law.

In theory, the emperor and the senate were two equal branches of government, but the actual authority of the senate was negligible and it was largely a vehicle through which the emperor disguised his autocratic powers under a cloak of republicanism. Still prestigious and respected, the Senate was largely a glorified rubber stamp institution which had been stripped of most of its powers, and was largely at the emperor's mercy.

Many emperors showed a certain degree of respect towards this ancient institution, while others were notorious for ridiculing it. During senate meetings, the emperor sat between the two consuls, and usually acted as the presiding officer. Higher ranking senators spoke before lower ranking senators, although the emperor could speak at any time. By the third century, the senate had been reduced to a glorified municipal body.

Senators and equestrians
No emperor could rule the empire without the Senatorial order and the Equestrian order. Most of the more important posts and offices of the government were reserved for the members of these two aristocratic orders. It was from among their ranks that the provincial governors, legion commanders, and similar officials were chosen.

These two classes were hereditary and mostly closed to outsiders. Very successful and favoured individuals could enter, but this was a rare occurrence. The careers of the young aristocrats was influenced by their family connections and the favour of patrons. As important as ability, knowledge, skill, or competence; patronage was considered vital for a successful career and the highest posts and offices required the emperor's favour and trust.

Senatorial order
The son of a senator was expected to follow the Cursus honorum, a career ladder, and the more prestigious positions were restricted to senators only. A senator also had to be wealthy; one of the basic requirements was the wealth of 12,000 gold aurei (about 100 kg of gold), a figure which would later be raised with the passing of centuries.

Equestrian order
Below the Senatorial order was the Equestrian order. The requirements and posts reserved for this class, while perhaps not so prestigious, were still very important. Some of the more vital posts, like the governorship of Aegyptus, were even forbidden to the members of the Senatorial order and available only to equestrians.

Legions
During and after the civil war, Octavian reduced the huge number of the legions (over 60) to a much more manageable and affordable size (28). Several legions, particularly those with doubtful loyalties, were simply disbanded. Other legions were amalgamated, a fact suggested by the title Gemina (Twin).

In AD 9, Germanic tribes wiped out three full legions in the Battle of the Teutoburg Forest. This disastrous event reduced the number of the legions to 25. The total of the legions would later be increased again and for the next 300 years always be a little above or below 30.

Augustus also created the Praetorian Guard: nine cohorts ostensibly to maintain the public peace which were garrisoned in Italy. Better paid than the legionaries, the Praetorians also served less time; instead of serving the standard 25 years of the legionaries, they retired after 16 years of service.

Auxillia
While the Auxillia (Latin: auxilia = supports) are not as famous as the legionaries, they were of major importance. Unlike the legionaries, the auxilia were recruited from among the non-citizens. Organized in smaller units of roughly cohort strength, they were paid less than the legionaries, and after 25 years of service were rewarded with Roman citizenship, also extended to their sons. According to Tacitus there were roughly as many auxiliaries as there were legionaries. Since at this time there were 25 legions of around 5,000 men each, the auxilia thus amounted to around 125,000 men, implying approximately 250 auxiliary regiments.

Navy
The Roman Navy (Latin: Classis, lit. "fleet") not only aided in the supply and transport of the legions, but also helped in the protection of the frontiers in the rivers Rhine and Danube. Another of its duties was the protection of the very important maritime trade routes against the threat of pirates. Therefore it patrolled the whole of the Mediterranean Sea, parts of the North Atlantic (coasts of Hispania, Gaul, and Britannia), and had also a naval presence in the Black Sea. Nevertheless the army was considered the senior and more prestigious branch.

Provinces
In the old days of the Republic the governorships of the provinces were traditionally awarded to members of the Senatorial Order. Augustus' reforms changed this policy.

Imperial provinces
Augustus created the Imperial provinces. Most, but not all, of the Imperial provinces were relatively recent conquests and located at the borders. Thereby the overwhelming majority of legions, which were stationed at the frontiers, were under direct Imperial control. Very important was the Imperial province of Aegyptus (modern Egypt), the major breadbasket of the empire, whose grain supply was vital to feed the masses in Rome. It was considered the personal fiefdom of the emperor, and Senators were forbidden to even visit this province. The governor of Aegyptus and the commanders of any legion stationed there were not from the Senatorial Order, but were chosen by the emperor from among the members of the lower Equestrian Order.

Senatorial provinces
The old traditional policy continued largely unchanged in the Senatorial provinces. Due to their location, away from the borders, and to the fact that they were under longer Roman sovereignty and control, these provinces were largely peaceful and stable. Only a single legion was based in a Senatorial province: Legio III Augusta, stationed in the Senatorial province of Africa (modern northern Algeria).

The status of a province was subject to change; it could change from Senatorial towards Imperial, or vice-versa. This happened several times during Augustus' reign. Another trend was to create new provinces, mostly by dividing older ones, or by expanding the empire.

Religion
As the empire expanded, and came to include people from a variety of cultures, the worship of an ever increasing number of deities was tolerated and accepted. The imperial government, and the Romans in general, tended to be very tolerant towards most religions and cults, so long as they did not cause trouble. This could easily be accepted by other faiths as Roman liturgy and ceremonies were frequently tailored to fit local culture and identity.

An individual could attend to both the Roman Gods representing his Roman identity and his own personal faith, which was considered part of his personal identity. There were periodic persecutions of various religions at various points in time, most notably that of Christians. As the historian Edward Gibbon noted, however, most of the recorded histories of Christian persecutions come to us through the Christian church, which had an incentive to exaggerate the degree to which the persecutions occurred. The non-Christian contemporary sources only mention the persecutions passingly and without assigning great importance to them.

Imperial cult
In an effort to enhance loyalty, the inhabitants of the empire were called to participate in the Imperial cult to revere (usually deceased) emperors as demigods. Few emperors claimed to be Gods while living, with the few exceptions being emperors who were widely regarded at the time to be insane (such as Caligula). Doing so in the early empire would have risked revealing the shallowness of what the emperor Augustus called the "restored republic" and would have had a decidedly eastern quality to it. It was, for example, his attempt to make himself a god (in the mold of the kings of the Achaemenid Persian Empire, which he had conquered) that helped to turn Alexander the Great's troops against him. Since the tool was mostly one the emperor used to control his subjects, its usefulness was greatest in the chaotic later empire, when the emperors were often Christians and unwilling to participate in the practice.

Usually, an emperor was deified after his death by his successor in an attempt by that successor to enhance his own prestige. This practice can be misunderstood, however, since "deification" was to the ancient world what canonization is to the Christian world. Likewise, the term "God" had a different context in the ancient world. This could be seen during the years of the Roman Republic with religio-political practices such as the disbanding of a senate session if it was believed the Gods disapproved of the session or wished a particular vote. Deification was one of the many honors a dead emperor was entitled to, as the Romans (more than modern societies) placed great prestige on honors and national recognitions.

The importance of the Imperial cult slowly grew, reaching its peak during the Crisis of the Third Century. Especially in the eastern half of the empire imperial cults grew very popular. As such it was one of the major agents of romanization. The central elements of the cult complex were next to a temple; a theatre or amphitheatre for gladiator displays and other games and a public bath complex. Sometimes the imperial cult was added to the cults of an existing temple or celebrated in a special hall in the bath complex.

The seriousness of this belief is unclear. Some Romans ridiculed the notion that a Roman emperor was to be considered a living god, or would even make fun of the deification of an emperor after his death. Seneca the Younger parodied the notion of apotheosis in his only known satire The Pumpkinification of Claudius, in which the clumsy and ill-spoken Claudius is not transformed into a god, but into a pumpkin. In fact, bitter sarcasm was already effected at Claudius' funeral in 54.

Absorption of foreign cults
Since Roman religion did not have a core belief that excluded other religions several foreign gods and cults became popular.

The worship of Cybele was the earliest, introduced from around BC 200. Isis and Osiris were introduced from Egypt a century later. Bacchus and Sol Invictus were quite important and Mithras became very popular with the military. Several of these were Mystery cults. In the first century BC Julius Caesar granted Jews the freedom to worship in Rome as a reward for their help in Alexandria.

Druids
Druids were seen as essentially non-Roman: a prescript of Augustus forbade Roman citizens to practice "druidical" rites. Pliny reports that under Tiberius the druids were suppressed—along with diviners and physicians—by a decree of the Senate, and Claudius forbade their rites completely in AD 54.

Judaism
While Judaism was largely accepted, it was on occasion subject to (mostly) local persecution.

Until the rebellion in Judea in AD 66, Jews were generally protected. To get around Roman laws banning secret societies and to allow their freedom of worship, Julius Caesar declared Synagogues were colleges. Tiberius forbade Judaism in Rome but they quickly returned to their former protected status. Claudius expelled Jews from the city however the passage of Suetonius is ambiguous: "Because the Jews at Rome caused continuous disturbances at the instigation of Chrestus he [Claudius] expelled them from the city". Chrestus has been identified as another form of Christus; the disturbances may have been related to the arrival of the first Christians, and that the Roman authorities, failing to distinguish between the Jews and the early Christians, simply decided to expel them all.

Christianity
Christianity, originally a Jewish religious sect, emerged in Roman Judea in the first century AD. The religion gradually spread out of Judea, initially establishing major bases in first Antioch, then Alexandria, and over time throughout the Empire. For the first two centuries, the imperial authorities largely viewed Christianity simply as a Jewish sect rather than a distinct religion. Suetonius mentions passingly that: "[during Nero's reign] Punishments were also inflicted on the Christians, a sect professing a new and mischievous religious belief" but he does not explain for what they were punished.

Tacitus reports that after the Great Fire of Rome in AD 64 some in the population held Nero responsible and that to diffuse blame, he targeted and blamed the Christians. The war against the Jews during Nero's reign, which so destabilized the empire that it led to the first civil war since the days of Julius Caesar and Mark Antony, as well as Nero's suicide, plausibly provided an additional rationale for persecutions against this 'Jewish' sect.

Persecution of Christians would be a recurring theme in the Empire for the next two centuries. Eusebius and Lactantius document the last great persecution of the Christians under Diocletian at the beginning of the 4th century at the urging of Galerius. This was the most vicious persecution of Christians in the Empire's history. After Diocletian, however, the fact that emperors were often Christians themselves lessened whatever persecutions may have still been occurring.

As the 4th century progressed, Christianity had become so widespread that it became officially tolerated, then promoted (Constantine I), and in 380 established as the Empire's official religion (Theodosius I). By the 5th century Christianity had become the Empire's predominant religion rapidly changing the Empire's identity even as the Western provinces collapsed. This would lead to the persecution of the traditional polytheistic religions that had previously characterized most of the Empire.

Languages
The language of Rome before its expansion was Latin, and this became the empire's official language. By the time of the imperial period Latin began evolving into two languages: the 'high' written Classical Latin and the 'low' spoken Vulgar Latin. While Classical Latin remained relatively stable, even through the Middle Ages, Vulgar Latin as with any spoken language was fluid and evolving. Vulgar Latin became the lingua franca in the western provinces, later evolving into the modern Romance languages: Italian, French, Portuguese, Spanish, Romanian, etc. Greek and Classical Latin were considered the languages of literature, scholarship, and education.

Although Latin remained the official and most widely spoken language through to the fall of Rome and for some centuries after in the East, the Greek language was the literary language and sometimes the lingua franca in the Eastern Provinces. With the exception of Carthage, the Romans generally did not attempt to supplant local cultures and languages. It is to their credit that they generally left established customs in place and only gradually supplemented with the typical Roman-style improvements. . Along with Greek, many other languages of different tribes were used but almost without expression in writing.

Greek was already widely spoken in many cities in the east, and as such, the Romans were quite content to retain it as an administrative language there rather than impede bureaucratic efficiency. Hence, two official secretaries served in the Roman Imperial court, one charged with correspondence in Latin and the other with correspondence in Greek for the East. Thus in the Eastern Province, as with all provinces, original languages were retained.

Moreover, the process of hellenisation continued more extensively during the Roman period, for the Romans perpetuated "Hellenistic" culture,  but with all the trappings of Roman improvements. This further spreading of "Hellenistic" culture (and therefore language) was largely due to the extensive infrastructure (in the form of entertainment, health, and education amenities, and extensive transportation networks, etc.) put in place by the Romans and their tolerance of, and inclusion of, other cultures, a characteristic which set them apart from the xenophobic nature of the Greeks preceding them.

Since the Roman annexation of Greece in 146 BC, the Greek language gradually obtained a unique place in the Roman world, owing initially to the large number of Greek slaves in Roman households. In Rome itself Greek became the second language of the educated elite. It became the common language in the early Church (as its major centers in the early Christian period were in the East), and the language of scholarship and the arts.

However, due to the presence of other widely spoken languages in the densely populated east, such as Coptic, Syriac, Armenian, Aramaic and Phoenician (which was also extensively spoken in North Africa), Greek never took as strong a hold beyond Asia Minor (some urban enclaves notwithstanding) as Latin eventually did in the west. This is partly evident in the extent to which the derivative languages are spoken today. Like Latin, the language gained a dual nature with the literary language, an Attic Greek variant, existing alongside spoken language, Koine Greek, which evolved into Medieval or Byzantine Greek (Romaic).

By the 4th century AD, Greek no longer held such dominance over Latin in the Church, arts and sciences as it had previously, resulting to a great extent from the growth of the western provinces (reflected, for example, in the publication in the early 5th century AD of the Vulgate Bible, the first officially accepted Latin Bible; before this only Greek translations were accepted). As the Western Empire declined, the number of people who spoke both Greek and Latin declined as well, contributing greatly to the future East–West / Orthodox–Catholic cultural divide in Europe.

Important as both languages were, today the descendants of Latin are widely spoken in many parts of the world, while the Greek dialects are limited mostly to Greece, Cyprus, and small enclaves in Turkey and southern Italy. To some degree this can be attributed to the fact that the western provinces fell mainly to "Latinised" Christian tribes whereas the eastern provinces fell to Muslim Arabs and Turks for whom Greek held less cultural significance.

Culture


Life in the Roman Empire revolved around the city of Rome, and its famed seven hills. The city also had several theatres. gymnasiums, and many taverns, baths and brothels. Throughout the territory under Rome's control, residential architecture ranged from very modest houses to country villas, and in the capital city of Rome, to the residences on the elegant Palatine Hill, from which the word "palace" is derived. The vast majority of the population lived in the city centre, packed into apartment blocks.

Most Roman towns and cities had a forum and temples, as did the city of Rome itself. Aqueducts were built to bring water to urban centresKevin Greene, “Technological Innovation and Economic Progress in the Ancient World: M.I. Finley Re-Considered”, The Economic History Review, New Series, Vol. 53, No. 1. (Feb., 2000), pp. 29–59 (39) and wine and oil were imported from abroad. Landlords generally resided in cities and their estates were left in the care of farm managers. To stimulate a higher labour productivity, many landlords freed a large numbers of slaves. By the time of Augustus, cultured Greek household slaves taught the Roman young (sometimes even the girls). Greek sculptures adorned Hellenistic landscape gardening on the Palatine or in the villas.

Many aspects of Roman culture were taken from the Greeks. In architecture and sculpture, the difference between Greek models and Roman paintings are apparent. The chief Roman contributions to architecture were the arch and the dome.

The centre of the early social structure was the family, which was not only marked by blood relations but also by the legally constructed relation of patria potestas. The Pater familias was the absolute head of the family; he was the master over his wife, his children, the wives of his sons, the nephews, the slaves and the freedmen, disposing of them and of their goods at will, even putting them to death. Originally, only patrician aristocracy enjoyed the privilege of forming familial clans, or gens, as legal entities; later, in the wake of political struggles and warfare, clients were also enlisted. Thus, such plebian gentes were the first formed, imitating their patrician counterparts.

Slavery and slaves were part of the social order; there were slave markets where they could be bought and sold. Many slaves were freed by the masters for services rendered; some slaves could save money to buy their freedom. Generally mutilation and murder of slaves was prohibited by legislation. It is estimated that over 25% of the Roman population was enslaved. Professor Gerhard Rempel from the Western New England College claims that in the city of Rome alone, during the Empire, there were about 400,000 slaves.

The city of Rome had a place called the Campus Martius ("Field of Mars"), which was a sort of drill ground for Roman soldiers. Later, the Campus became Rome’s track and field playground. In the campus, the youth assembled to play and exercise, which included jumping, wrestling, boxing and racing. Riding, throwing, and swimming were also preferred physical activities.

In the countryside, pastime also included fishing and hunting. Board games played in Rome included Dice (Tesserae or Tali), Roman Chess (Latrunculi), Roman Checkers (Calculi), Tic-tac-toe (Terni Lapilli), and Ludus duodecim scriptorum and Tabula, predecessors of backgammon. There were several other activities to keep people engaged like chariot races, musical and theatrical performances,

Clothing, dining, and the arts
The cloth and the dress distinguished one class of people from the other class. The tunic worn by plebeians (common people) like shepherds and slaves was made from coarse and dark material, whereas the tunic worn by patricians was of linen or white wool. A magistrate would wear the tunic augusticlavi; senators wore a tunic with broad stripes, called tunica laticlavi. Military tunics were shorter than the ones worn by civilians. Boys, up until the festival of Liberalia, wore the toga praetexta, which was a toga with a crimson or purple border. The toga virilis, (or toga pura) was worn by men over the age of 16 to signify their citizenship in Rome.

The toga picta was worn by triumphant generals and had embroidery of their skill on the battlefield. The toga pulla was worn when in mourning. Even footwear indicated a person’s social status. Patricians wore red and orange sandal, senators had brown footwear, consuls had white shoes, and soldiers wore heavy boots. Men typically wore a toga, and women a stola. The woman's stola looked different than a toga, and was usually brightly coloured. The Romans also invented socks for those soldiers required to fight on the northern frontiers, sometimes worn in sandals.

Romans had simple food habits. Staple food was simple, generally consumed at around 11 o’clock, and consisted of bread, salad, cheese, fruits, nuts, and cold meat left over from the dinner the night before. The Roman poet, Horace mentions another Roman favourite, the olive, in reference to his own diet, which he describes as very simple: "As for me, olives, endives, and smooth mallows provide sustenance." The family ate together, sitting on stools around a table. Fingers were used to eat solid foods and spoons were used for soups.

Wine was considered a staple drink, consumed at all meals and occasions by all classes and was quite cheap. Many types of drinks involving grapes and honey were consumed as well. Drinking on an empty stomach was regarded as boorish and a sure sign for alcoholism, whose debilitating physical and psychological effects were known to the Romans. An accurate accusation of being an alcoholic was an effective way to discredit political rivals.

Roman literature was from its very inception influenced heavily by Greek authors. Some of the earliest works we possess are of historical epics telling the early military history of Rome. As the empire expanded, authors began to produce poetry, comedy, history, and tragedy. Virgil represents the pinnacle of Roman epic poetry. His Aeneid tells the story of flight of Aeneas from Troy and his settlement of the city that would become Rome. Lucretius, in his On the Nature of Things, attempted to explicate science in an epic poem. The genre of satire was common in Rome, and satires were written by, among others, Juvenal and Persius. Many Roman homes were decorated with landscapes by Greek artists. Portrait sculpture during the period utilized youthful and classical proportions, evolving later into a mixture of realism and idealism. Advancements were also made in relief sculptures, often depicting Roman victories.

Music was a major part of everyday life. The word itself derives from Greek μουσική (mousike), "(art) of the Muses". Many private and public events were accompanied by music, ranging from nightly dining to military parades and manoeuvres. In a discussion of any ancient music, however, non-specialists and even many musicians have to be reminded that much of what makes our modern music familiar to us is the result of developments only within the last 1,000 years; thus, our ideas of melody, scales, harmony, and even the instruments we use would not be familiar to Romans who made and listened to music many centuries earlier.

Over time, Roman architecture was modified as their urban requirements changed, and the civil engineering and building construction technology became developed and refined. The Roman concrete has remained a riddle, and even after more than 2,000 years some Roman structures still stand magnificently. The architectural style of the capital city was emulated by other urban centres under Roman control and influence.

Education
Following various military conquests in the Greek East, Romans adapted a number of Greek educational precepts to their own fledgling system. Home was often the learning centre, where children were taught Roman law, customs, and physical training to prepare the boys to grow as Roman citizens and for eventual recruitment into the army. Conforming to discipline was a point of great emphasis. Girls generally received instruction from their mothers in the art of spinning, weaving, and sewing.

Education began at the age of around six, and in the next six to seven years, boys and girls were expected to learn the basics of reading, writing and counting. By the age of twelve, they would be learning Latin, Greek, grammar and literature, followed by training for public speaking. Oratory was an art to be practised and learnt, and good orators commanded respect. To become an effective orator was one of the objectives of education and learning. In some cases, services of gifted slaves were utilized for imparting education.

Economy
The imperial government was, as all governments, interested in the issue and control of the currency in circulation. To mint coins was a political act: the image of the ruling emperor appeared on most issues, and coins were a means of showing his image throughout the empire. Also featured were predecessors, empresses, other family members, and heirs apparent. By issuing coins with the image of an heir his legitimacy and future succession was proclaimed and reinforced. Political messages and imperial propaganda such as proclamations of victory and acknowledgements of loyalty also appeared in certain issues.

Legally only the emperor and the Senate had the authority to mint coins inside the empire. However the authority of the Senate was mainly in name only. In general, the imperial government issued gold and silver coins while the Senate issued bronze coins marked by the legend "SC", short for Senatus Consulto "by decree of the Senate". However, bronze coinage could be struck without this legend. Some Greek cities were allowed to mint bronze and certain silver coins, which today are known as Greek Imperials (also Roman Colonials or Roman Provincials). The imperial mints were under the control of a chief financial minister, and the provincial mints were under the control of the imperial provincial procurators. The Senatorial mints were governed by officials of the Senatorial treasury.

Demography
In recent years, question relating to ancient demographics have received increasingly more scholarly attention, with estimates of the population size of the Roman empire at its demographic peak now varying between 60-70 million ("low count") and over 100 million ("high count"). Even by adhering to the more traditional value of 55 million inhabitants, the Roman Empire constituted the most populous Western political unity until the mid-19th century and on a global scale probably until around AD 1000.

Augustus (27 BC–AD 14)
The Battle of Actium resulted in the defeat and subsequent suicides of Mark Antony and Cleopatra. Octavian, now sole ruler of Rome, began a full-scale reformation of military, fiscal and political matters. The powers that he secured for himself were identical in form, if not in name, to those that his predecessor Julius Caesar had secured years earlier as Roman Dictator.

In 36 BC, he was given the power of a Plebeian Tribune, which gave him veto power over the senate, the ability to control the principle legislative assembly (the Plebeian Council), and made his person and office sacrosanct. Up until 32 BC, his status as a Triumvir gave him the powers of an autocrat, but when he deposed Mark Antony that year, he resigned from the Triumvirate, and was then given powers identical to those that he had given up. In 29 BC, Octavian was given the authority of a Roman Censor, and thus the power to appoint new senators.

The senate granted Octavian a unique grade of Proconsular imperium, which gave him authority over all Proconsuls (military governors). The unruly provinces at the borders, where the vast majority of the legions were stationed, were under the control of Augustus. These provinces were classified as imperial provinces. The peaceful senatorial provinces were under the control of the Senate. The Roman legions, which had reached an unprecedented number (around 50) because of the civil wars, were reduced to 28.

Augustus also created nine special cohorts, ostensibly to maintain the peace in Italy, keeping at least three of them stationed at Rome. These cohorts became known as the Praetorian Guard. In 27 BC, Octavian transferred control of the state back to the Senate and the People of Rome. The Senate refused the offer, which, in effect, functioned as a popular ratification of his position within the state. Octavian was also granted the title of "Augustus" by the senate, and took the title of Princeps, or "first citizen".

As the adopted heir of Caesar, Augustus preferred to be called by this name. Caesar was a component of his family name. Julio-Claudian rule lasted for almost a century (from Julius Caesar in the mid-1st century BC to the emperor Nero in the mid-1st century AD). By the time of the Flavian Dynasty, and the reign of Vespasian, and that of his two sons, Titus and Domitian, the term Caesar had evolved, almost de facto, from a family name into a formal title.

Augustus' final goal was to figure out a method to ensure an orderly succession. In 6 BC Augustus granted tribunician powers to his stepson Tiberius, and before long Augustus realized that he had no choice but to recognize Tiberius as his heir. In AD 13, the point was settled beyond question. A law was passed which linked Augustus' powers over the provinces to those of Tiberius, so that now Tiberius' legal powers were equivalent to, and independent from, those of Augustus. Within a year, Augustus was dead.

Tiberius to Alexander Severus (14–235)
Augustus was succeeded by his stepson Tiberius, the son of his wife Livia from her first marriage. Augustus was a scion of the gens Julia (the Julian family), one of the most ancient patrician clans of Rome, while Tiberius was a scion of the gens Claudia, only slightly less ancient than the Julians. Their three immediate successors were all descended both from the gens Claudia, through Tiberius's brother Nero Claudius Drusus, and from gens Julia, either through Julia the Elder, Augustus's daughter from his first marriage (Caligula and Nero), or through Augustus's sister Octavia Minor (Claudius). Historians thus refer to their dynasty as "Julio-Claudian Dynasty".

The early years of Tiberius's reign were peaceful and relatively benign. However, Tiberius's reign soon became characterised by paranoia and slander. He began a series of treason trials and executions, which continued until his death in 37. The logical successor to the hated Tiberius was his grandnephew, Gaius (better known as "Caligula" or "little boots"). Caligula started out well, but quickly became insane. In 41 Caligula was assassinated, and for two days following his assassination, the senate debated the merits of restoring the republic.

Due to the demands of the army, however, Claudius was ultimately declared emperor. Claudius was neither paranoid like his uncle Tiberius, nor insane like his nephew Caligula, and was therefore able to administer the empire with reasonable ability. In his own family life he was less successful, as he married his niece, who may very well have poisoned him in 54. Nero, who succeeded Claudius, focused much of his attention on diplomacy, trade, and increasing the cultural capital of the empire. Nero, though, is remembered as a tyrant, and committed suicide in 68.

The forced suicide of Nero was followed by a brief period of civil war, known as the "Year of the Four Emperors". Augustus had established a standing army, where individual soldiers served under the same military governors over an extended period of time. The consequence was that the soldiers in the provinces developed a degree of loyalty to their commanders, which they did not have for the emperor. Thus the empire was, in a sense, a union of inchoate principalities, which could have disintegrated at any time. Between June 68 and December 69, Rome witnessed the successive rise and fall of Galba, Otho and Vitellius until the final accession of Vespasian, first ruler of the Flavian dynasty. These events showed that any successful general could legitimately claim a right to the throne.

Vespasian, though a successful emperor, continued the weakening of the Senate which had been going on since the reign of Tiberius. Through his sound fiscal policy, he was able to build up a surplus in the treasury, and began construction on the Colosseum. Titus, Vespasian's successor, quickly proved his merit, although his short reign was marked by disaster, including the eruption of Mount Vesuvius in Pompeii. He held the opening ceremonies in the still unfinished Colosseum, but died in 81. He was succeeded by his brother, Domitian, who had exceedingly poor relations with the senate. Domitian, ultimately, was a tyrant with the character which always makes tyranny repulsive, and this derived in part from the fact that he had no son, and thus was constantly in danger of being overthrown. In September of 96, he was murdered.

The next century came to be known as the period of the "Five Good Emperors", in which the successions were peaceful and the Empire was prosperous. Each emperor of this period was adopted by his predecessor. The last 2 of the "Five Good Emperors" and Commodus are also called Antonines. After his accession, Nerva, who succeeded Domitian, set a new tone: he restored much confiscated property and involved the Roman Senate in his rule.

In 112, Trajan marched on Armenia and annexed it to the Roman Empire. Then he turned south into Parthia, taking several cities before declaring Mesopotamia a new province of the empire, and lamenting that he was too old to follow in the steps of Alexander the Great. During his rule, the Roman Empire was to its largest extent, and would never again advance so far to the east. Hadrian's reign was marked by a general lack of major military conflicts, but he had to defend the vast territories that Trajan had acquired.

Antoninus Pius's reign was comparatively peaceful. During the reign of Marcus Aurelius, Germanic tribes launched many raids along the northern border. The period of the "Five Good Emperors" also commonly described as the Pax Romana, or "Roman Peace" was brought to an end by the reign of Commodus. Commodus was the son of Marcus Aurelius, breaking the scheme of adoptive successors that had turned out so well. Commodus became paranoid and slipped into insanity before being murdered in 192.

The Severan Dynasty, which lasted from 193 until 235, included several increasingly troubled reigns. A generally successful ruler, Septimius Severus, the first of the dynasty, cultivated the army's support and substituted equestrian officers for senators in key administrative positions. His son, Caracalla, extended full Roman citizenship to all free inhabitants of the empire. Increasingly unstable and autocratic, Caracalla was assassinated by Macrinus, who succeeded him, before being assassinated and succeeded by Elagabalus. Alexander Severus, the last of the dynasty, was increasing unable to control the army, and was assassinated in 235.

Crisis of the Third Century and the later emperors (235–395)
The Crisis of the Third Century is a commonly applied name for the crumbling and near collapse of the Roman Empire between 235 and 284. During this time, 25 emperors reigned, and the empire experienced extreme military, political, and economic crises. Additionally, in 251, the Plague of Cyprian broke out, causing large-scale mortality which may have seriously affected the ability of the Empire to defend itself. This period ended with the accession of Diocletian, who reigned from 284 until 305, and who solved many of the acute problems experienced during this crisis.

However, the core problems would remain and cause the eventual destruction of the western empire. Diocletian saw the vast empire as ungovernable, and therefore split the empire in half and created two equal emperors to rule under the title of Augustus. In doing so, he effectively created what would become the Western Roman Empire and the Eastern Roman Empire. In 293 authority was further divided, as each Augustus took a junior Emperor called a Caesar to provide a line of succession. This constituted what is now known as the Tetrarchy ("rule of four"). The transitions of this period mark the beginnings of Late Antiquity.

The Tetrarchy would effectively collapse with the death of Constantius Chlorus, the first of the Constantinian dynasty, in 306. Constantius's troops immediately proclaimed his son Constantine the Great as Augustus. A series of civil wars broke, which ended with the entire empire being united under Constantine, who legalised Christianity definitively in 313 through the Edict of Milan.

In 361, after decades of further civil war, Julian became emperor. His edict of toleration in 362 ordered the reopening of pagan temples, and, more problematically for the Christian Church, the recalling of previously exiled Christian bishops. Julian eventually resumed the war against Shapur II of Persia, although he received a mortal wound in battle and died in 363. His officers then elected Jovian emperor. Jovian is remembered for ceding terrorities won from the Persians, dating back to Trajan, and for restoring the privileges of Christianity, before dying in 364.

Upon Jovian's death, Valentinian I, the first of the Valentinian dynasty, was elected Augustus, and chose his brother Valens to serve as his co-emperor. In 365, Procopius managed to bribe two legions, who then proclaimed him Augustus. War between the two rival Eastern Roman Emperors continued until Procopius was defeated, although in 367, eight-year-old Gratian was proclaimed emperor by the other two. In 375 Valentinian I led his army in a campaign against a Germanic tribe, but died shortly thereafter. Succession did not go as planned. Gratian was then a 16-year-old and arguably ready to act as Emperor, but the troops proclaimed his infant half-brother emperor under the title Valentinian II, and Gratian acquiesced.

Meanwhile, the Eastern Roman Empire faced its own problems with Germanic tribes. One tribe fled their former lands and sought refuge in the Eastern Roman Empire. Valens let them settle on the southern bank of the Danube in 376, but they soon revolted against their Roman hosts. Valens personally led a campaign against them in 378. However this campaign proved disastrous for the Romans. The two armies approached each other near Adrianople, but Valens was apparently overconfident of the numerical superiority of his own forces over the enemy. Valens, eager to have all of the glory for himself, rushed into battle, and on 9 August 378, the Battle of Adrianople resulted in a crushing defeat for the Romans, and the death of Valens.

Contemporary historian Ammianus Marcellinus estimated that two thirds of the Roman army were lost in the battle. The battle had far-reaching consequences, as veteran soldiers and valuable administrators were among the heavy casualties, which left the Empire with the problem of finding suitable leadership. Gratian was now effectively responsible for the whole of the Empire. He sought however a replacement Augustus for the Eastern Roman Empire, and in 379 choose Theodosius I.

Theodosius, the founder of the Theodosian dynasty, proclaimed his five year old son Arcadius an Augustus in 383 in an attempt to secure succession. Hispanic Celt general Magnus Maximus, stationed in Roman Britain, was proclaimed Augustus by his troops in 383 and rebelled against Gratian when he invaded Gaul. Gratian fled, but was assassinated. Following Gratian's death, Maximus had to deal with Valentinian II, at the time only twelve years old, as the senior Augustus. Maximus soon entered negotiations with Valentinian II and Theodosius, attempting to gain their official recognition, although Negotiations were unfruitful. Theodosius campaigned west in 388 and was victorious against Maximus, who was then captured and executed. In 392 Valentinian II was murdered, and shortly thereafter Arbogast arranged for the appointment of Eugenius as emperor.

However, the eastern emperor Theodosius I refused to recognise Eugenius as emperor and invaded the West, defeating and killing Arbogast and Eugenius. He thus reunited the entire Roman Empire under his rule. Theodosius was the last Emperor who ruled over the whole Empire. As emperor, he made Christianity the official religion of the Roman Empire. After his death in 395, he gave the two halves of the Empire to his two sons Arcadius and Honorius. The Roman state would continue to have two different emperors with different seats of power throughout the 5th century, though the Eastern Romans considered themselves Roman in full. The two halves were nominally, culturally and historically, if not politically, the same state.

Decline of the Western Roman Empire (395–476)
After 395, the emperors in the Western Roman Empire were usually figureheads, while the actual rulers were military strongmen. The year 476 is generally accepted as the formal end of the Western Roman Empire. That year, Orestes refused the request of Germanic mercenaries in his service for lands in Italy. The dissatisfied mercenaries, led by Odoacer, revolted, and deposed the last western emperor, Romulus Augustus. This event has traditionally been considered the fall of the Western Roman Empire.

Odoacer quickly conquered the remaining provinces of Italy, and then sent the Imperial Regalia back to the Eastern Roman Emperor Zeno. Zeno soon received two deputations. One was from Odoacer, requesting that his control of Italy be formally recognised by the Empire, in which case he would acknowledge Zeno's supremacy. The other deputation was from Nepos, the emperor before Romulus Augustus, asking for support to regain the throne. Zeno granted Odoacer's request. Upon Nepos's death in 480, Zeno claimed Dalmatia for the East. Odoacer attacked Dalmatia, and the ensuing war ended with Theodoric the Great, King of the Ostrogoths, conquering Italy.

The Empire became gradually less Romanised and increasingly Germanic in nature: although the Empire buckled under Visigothic assault, the overthrow of the last Emperor Romulus Augustus was carried out by federated Germanic troops from within the Roman army rather than by foreign troops. In this sense had Odoacer not renounced the title of Emperor and named himself "King of Italy" instead, the Empire might have continued in name. Its identity, however, was no longer Roman—it was increasingly populated and governed by Germanic peoples long before 476.

The Roman people were by the fifth century "bereft of their military ethos" and the Roman army itself a mere supplement to federated troops of Goths, Huns, Franks and others fighting on their behalf. Many theories have been advanced in explanation of the decline of the Roman Empire, and many dates given for its fall, from the onset of its decline in the third century to the fall of Constantinople in 1453.

Militarily, however, the Empire finally fell after first being overrun by various non-Roman peoples and then having its heart in Italy seized by Germanic troops in a revolt. The historicity and exact dates are uncertain, and some historians do not consider that the Empire fell at this point. Disagreement persists since the decline of the Empire had been a long and gradual process rather than a single event.

Eastern Roman Empire (476–1453)
As the Western Roman Empire declined during the 5th century, the richer Eastern Roman Empire would be relieved of much destruction, and in the mid 6th century the Eastern Roman Empire (known also as the Byzantine Empire) under the emperor Justinian I reconquered Italy and parts of Illyria from the Ostrogoths, North Africa from the Vandals, and southern Hispania from the Visigoths. The reconquest of southern Hispania was somewhat ephemeral, but North Africa served the Byzantines for another century, parts of Italy for another 5 centuries, and parts Illyria even longer.

Of the many accepted dates for the end of the classical Roman state, the latest is 610. This is when the Emperor Heraclius made sweeping reforms, forever changing the face of the empire. Greek was readopted as the language of government and Latin influence waned. By 610, the Eastern Roman Empire had come under definite Greek influence, and could be considered to have become what many modern historians now call the Byzantine Empire; however, the Empire was never called thus by its inhabitants, who used terms such as Romania, Basileia Romaion or Pragmata Romaion, meaning "Land of the Romans", "Kingdom of the Romans", and who still saw themselves as Romans, and their state as the rightful successor to the ancient empire of Rome.

The sack of Constantinople at the hands of the Fourth Crusade in 1204 is sometimes used to date the end of Eastern Roman Empire: the destruction of Constantinople and most of its ancient treasures, total discontinuity of leadership, and the division of its lands into rival states with a Catholic-controlled "Emperor" in Constantinople itself was a blow from which the Empire never fully recovered. Nevertheless, the Byzantines continued to call themselves Romans until their fall to Ottoman Turks in 1453. That year the eastern part of the Roman Empire was ultimately ended by the Fall of Constantinople. Even though Mehmed II, the conqueror of Constantinople, declared himself the Emperor of the Roman Empire (Caesar of Rome / Kayser-i Rum) in 1453, Constantine XI is usually considered the last Roman Emperor. The Greek ethnic self-descriptive name "Rhomios" (Roman) survives to this day.

Principate (27 BC–AD 235)
Between the reigns of the emperors Augustus and Trajan, the Roman Empire achieved great territorial gains in both the East and the West. In the West, following several defeats in 16 BC, Roman armies pushed north and east out of Gaul to subdue much of Germania. Despite the loss of a large army almost to the man in Varus' famous defeat in the Battle of the Teutoburg Forest in AD 9,

Rome recovered and continued its expansion up to and beyond the borders of the known world. The Romans invaded Britain in AD 43, forcing their way inland, and building two military bases to protect against rebellion and incursions from the north, from which Roman troops built and manned Hadrian's Wall.

Emperor Claudius ordered the suspension of further attacks across the Rhine, setting what was to become the permanent limit of the Empire's expansion in this direction. Further east, Trajan turned his attention to Dacia. Following an uncertain number of battles, Trajan marched into Dacia, besieged the Dacian capital and razed it to the ground. With Dacia quelled, Trajan subsequently invaded the Parthian empire to the east, his conquests taking the Roman Empire to its greatest extent.

In AD 69, Marcus Salvius Otho had the Emperor Galba murdered and claimed the throne for himself,  but Vitellius had also claimed the throne. Otho left Rome, and met Vitellius at the First Battle of Bedriacum, after which the Othonian troops fled back to their camp, and the next day surrendered to the Vitellian forces. Meanwhile, the forces stationed in the Middle East provinces of Judaea and Syria had acclaimed Vespasian as emperor. Vespasians' and Vitellius' armies met in the Second Battle of Bedriacum, after which the Vitellian troops were driven back into their camp. Vespasian, having successfully ended the civil war, was declared emperor.

The First Jewish-Roman War, sometimes called The Great Revolt, was the first of three major rebellions by the Jews of Judaea Province against the Roman Empire. Earlier Jewish successes against Rome only attracted greater attention from Emperor Nero, who appointed general Vespasian to crush the rebellion. By the year 68, Jewish resistance in the North had been crushed. In 115, revolt broke out again in the province, leading to the second Jewish-Roman war known as the Kitos War, and again in 132 in what is known as Bar Kokhba's revolt. Both were brutally crushed.

Due in large part to their employment of powerful heavy cavalry and mobile horse-archers, the Parthian Empire was the most formidable enemy of the Roman Empire in the east. Trajan had campaigned against the Parthians and briefly captured their capital, putting a puppet ruler on the throne, but the territories were abandoned. A revitalised Parthian Empire renewed its assault in 161, and defeated two Roman armies. General Gaius Avidius Cassius was sent in 162 to counter the resurgent Parthia. The Parthian city of Seleucia on the Tigris was destroyed, and the Parthians made peace but were forced to cede western Mesopotamia to the Romans.

In 197, Emperor Septimius Severus waged a brief and successful war against the Parthian Empire, during which time the Parthian capital was sacked, and the northern half of Mesopotamia was restored to Rome. Emperor Caracalla marched on Parthia in 217 from Edessa to begin a war against them, but he was assassinated while on the march. In 224, the Parthian Empire was crushed not by the Romans but by the rebellious Persian vassal king Ardashir, who revolted, leading to the establishment of Sassanid Empire of Persia, which replaced Parthia as Rome's major rival in the East.

Barracks and Illyrian emperors (235-284) and Dominate (284–395)
Although the exact historicity is unclear, some mix of Germanic peoples, Celts, and tribes of mixed Celto-Germanic ethnicity were settled in the lands of Germania from the first century onwards. The essential problem of large tribal groups on the frontier remained much the same as the situation Rome faced in earlier centuries, the third century saw a marked increase in the overall threat.

The assembled warbands of the Alamanni frequently crossed the border, attacking Germania Superior such that they were almost continually engaged in conflicts with the Roman Empire. However, their first major assault deep into Roman territory did not come until 268. In that year the Romans were forced to denude much of their German frontier of troops in response to a massive invasion by another new Germanic tribal confederacy, the Goths, from the east. The pressure of tribal groups pushing into the Empire was the end result of a chain of migrations with its roots far to the east.

The Alamanni seized the opportunity to launch a major invasion of Gaul and northern Italy. However, the Visigoths were defeated in battle that summer and then routed in the Battle of Naissus. The Goths remained a major threat to the Empire but directed their attacks away from Italy itself for several years after their defeat.

The Alamanni on the other hand resumed their drive towards Italy almost immediately. They defeated Aurelian at the Battle of Placentia in 271 but were beaten back for a short time, only to reemerge fifty years later. In 378 the Goths inflicted a crushing defeat on the Eastern Empire at the Battle of Adrianople.

At the same time, Franks raided through the North Sea and the English Channel, Vandals pressed across the Rhine, Iuthungi against the Danube, Iazyges, Carpi and Taifali harassed Dacia, and Gepids joined the Goths and Heruli in attacks round the Black Sea. At the start of the fifth century AD, the pressure on Rome's western borders was growing intense.

A military that was often willing to support its commander over its emperor meant that commanders could establish sole control of the army they were responsible for and usurp the imperial throne. The so-called Crisis of the Third Century describes the turmoil of murder, usurpation and in-fighting that is traditionally seen as developing with the murder of the Emperor Alexander Severus in 235.

Emperor Septimius Severus was forced to deal with two rivals for the throne: Pescennius Niger and then Clodius Albinus. Severus' successor Caracalla passed uninterrupted for a while until he was murdered by Macrinus, who proclaimed himsef emperor in his place. The troops of Elagabalus declared him to be emperor instead, and the two met in battle at the Battle of Antioch in AD 218, in which Macrinus was defeated.

However, Elagabalus was murdered shortly afterwards and Alexander Severus was proclaimed emperor, who at the end of his reign was murdered in turn. His murderers raised in his place Maximinus Thrax. However, just as he had been raised by the army, Maximinus was also brought down by them and was murdered when it appeared to his forces as though he would not be able to best the senatorial candidate for the throne, Gordian III.

Gordian III's fate is not certain, although he may have been murdered by his own successor, Philip the Arab, who ruled for only a few years before the army again raised a general to proclaimed emperor, this time Decius, who defeated Philip in the Battle of Verona to seize the throne. Gallienus, emperor from AD 260 to 268, saw a remarkable array of usurpers. Diocletian, a usurper himself, defeated Carinus to become emperor. Some small measure of stability again returned at this point, with the empire split into a Tetrarchy of two greater and two lesser emperors, a system that staved off civil wars for a short time until AD 312. In that year, relations between the tetrarchy collapsed for good. From AD 314 onwards, Constantine the Great defeated Licinius in a series of battles. Constantine then turned to Maxentius, beating him in the Battle of Verona and the Battle of Milvian Bridge.

After overthrowing the Parthian confederacy, the Sassanid Empire that arose from its remains pursued a more aggressive expansionist policy than their predecessors  and continued to make war against Rome. In 230, the first Sassanid emperor attacked Roman territory, and in 243, Emperor Gordian III's army defeated the Sassanids at the Battle of Resaena.

In 253 the Sassanids under Shapur I penetrated deeply into Roman territory, defeating a Roman force at the Battle of Barbalissos and conquering and plundering Antiochia. In 260 at the Battle of Edessa the Sassanids defeated the Roman army and captured the Roman Emperor Valerian.

There was a lasting peace between Rome and the Sassanid Empire between 297 and 337 following a treaty between Narseh and Emperor Diocletian. However, just before the death of Constantine I in 337, Shapur II broke the peace and began a twenty-six year conflict, attempting with little success to conquer Roman fortresses in the region. Emperor Julian met Shapur in 363 in the Battle of Ctesiphon outside the walls of the Persian capital. The Romans were victorious but were unable to take the city and were forced to retreat. There were several later wars.

Collapse of the Western Empire (395–476)


After the death of Theodosius I in 395, the Visigoths renounced their treaty with the Empire and invaded northern Italy under their new king Alaric, but were repeatedly repulsed by the Western commander-in-chief Stilicho. However, the limes on the Rhine had been depleted of Roman troops, and in early 407 Vandals, Alans, and Suevi invaded Gaul en masse and, meeting little resistance, proceeded to cross the Pyrenees, entering Spain in 409.

Stilicho became a victim of court intrigues in Ravenna (where the imperial court resided since 402) and was executed for high treason in 408. After his death, the government became increasingly ineffective in dealing with the barbarians, and in 410 Rome was sacked by the Visigoths.

Under Alaric's successors, the Goths then settled in Gaul (412-418) as foederati and for a while were successfully employed against the Vandals, Alans, and Suevi in Spain. Meanwhile, in the turmoil of the preceding years, Roman Britain had been abandoned.

After Honorius' death in 423, the Eastern empire installed the weak Valentinian III as Western Emperor in Ravenna. After a violent struggle with several rivals, Aetius rose to the rank of magister militum. Aetius was able to stabilize the empire's military situation somewhat, relying heavily on his Hunnic allies. With their help he defeated the Burgundians, who had occupied part of southern Gaul after 407, and settled them as Roman allies in the Savoy (433). Later that century, as Roman power faded away, the Burgundians extended their rule to the Rhone valley.

Meanwhile, pressure from the Visigoths and a rebellion by the governor of Africa, Bonifacius, had induced the Vandals under their king Gaiseric to cross over from Spain in 429. After capturing Carthage, they established an independent state with a powerful navy (439), which was officially recognised by the Empire in 442. The Vandal fleet from then on formed a constant danger to Roman seafare and the coasts and islands of the Western and Central Mediterranean.

In 444, the Huns, who had been employed as Roman allies by Aetius, were united under their king Attila, who invaded Gaul and was only stopped with great effort by a combined Roman-Germanic force led by Aetius in the Battle of Chalons (451). The next year, Attila invaded Italy and proceeded to march upon Rome, but he halted his campaign and died a year later in 453.

Aetius was murdered by Valentinian in 454, who was then himself murdered by the dead general's supporters a year later. With the end of the Theodosian dynasty, a new period of dynastic struggle ensued. The Vandals took advantage of the unrest, sailed up to Rome, and plundered the city in 455. As the barbarians settled in the former provinces, nominally as allies but de facto operating as independent polities, the territory of the Western Empire was effectively reduced to Italy and parts of Gaul.

From 455 onward, several emperors were installed in the West by the government of Constantinople, but their authority only reached as far as the barbarian commanders of the army and their troops (Ricimer (456-472), Gundobad (473-475)) allowed it to. In 475, Orestes, a former secretary of Attila, drove Emperor Julius Nepos out of Ravenna and proclaimed his own son Romulus Augustus as emperor.

In 476, Orestes refused to grant Odoacer and the Heruli federated status, prompting the latter to kill him, depose his son and send the imperial insignia to Constantinople, installing himself as king over Italy. Although isolated pockets of Roman rule continued even after 476, the city of Rome itself was under the rule of the barbarians, and the control of Rome over the West had effectively ended. The Eastern Roman or Byzantine Empire endured until 1453 with the capture of Constantinople by the Ottoman Turks led by Mehmed II.

Legacy
The American magazine National Geographic described the legacy of the Roman Empire in The World According to Rome: "The enduring Roman influence is reflected pervasively in contemporary language, literature, legal codes, government, architecture, engineering, medicine, sports, arts, etc. Much of it is so deeply inbedded that we barely notice our debt to ancient Rome. Consider language, for example. Fewer and fewer people today claim to know Latin — and yet, go back to the first sentence in this paragraph. If we removed all the words drawn directly from Latin, that sentence would read; "The.""

Several states claimed to be the Roman Empire's successors after the fall of the Western Roman Empire. The Holy Roman Empire, an attempt to resurrect the Empire in the West, was established in 800 when Pope Leo III crowned Frankish King Charlemagne as Roman Emperor on Christmas Day, though the empire and the imperial office did not become formalised for some decades. After the fall of Constantinople, the Russian Tsardom, as inheritor of the Byzantine Empire's Orthodox Christian tradition, counted itself the third Rome (with Constantinople having been the second).

When the Ottomans, who based their state on the Byzantine model, took Constantinople in 1453, Mehmed II established his capital there and claimed to sit on the throne of the Roman Empire, and he even went so far as to launch an invasion of Italy with the purpose of "re-uniting the Empire", although Papal and Neapolitan armies stopped his march on Rome at Otranto in 1480. Constantinople was not officially renamed Istanbul until 28 March 1930.

Excluding these states claiming its heritage, if the traditional date for the founding of Rome is accepted as fact, the Roman state can be said to have lasted in some form from 753 BC to the fall in 1461 of the Empire of Trebizond (a successor state and fragment of the Byzantine Empire which escaped conquest by the Ottomans in 1453), for a total of 2,214 years. The Roman impact on Western and Eastern civilisations lives on. In time most of the Roman achievements were duplicated by later civilisations. For example, the technology for cement was rediscovered 1755–1759 by John Smeaton.

The Empire contributed many things to the world, such as a calendar with leap years, the institutions of Christianity and aspects of modern neo-classicistic and Byzantine architecture. The extensive system of roads that was constructed by the Roman Army lasts to this day. Because of this network of roads, the time necessary to travel between destinations in Europe did not decrease until the 19th century, when steam power was invented. Even modern astrology comes to us directly from the Romans.

The Roman Empire also contributed its form of government, which influences various constitutions including those of most European countries and many former European colonies. In the United States, for example, the framers of the Constitution remarked, in creating the Presidency, that they wanted to inaugurate an "Augustan Age". The modern world also inherited legal thinking from Roman law, fully codified in Late Antiquity. Governing a vast territory, the Romans developed the science of public administration to an extent never before conceived or necessary, creating an extensive civil service and formalised methods of tax collection.

While in the West the term "Roman" acquired a new meaning in connection with the church and the Pope of Rome the Greek form Romaioi remained attached to the Greek-speaking Christian population of the Eastern Roman Empire and is still used by Greeks in addition to their common appellation.

The Roman Empire's territorial legacy of controlling the Italian peninsula would serve as an influence to Italian nationalism and the unification (Risorgimento) of Italy in 1861.