10 key Roman dates you need to know

753 BC: The “foundation of Rome”

By the last century BC, Romans believed that Rome had been founded in exactly 753 BC. The story was that the twins Romulus and Remus, sons of the god Mars, were left to die by being put in a basket, set adrift on the river Tiber. The makeshift vessel eventually came ashore at the future site of Rome. Here, the babies were suckled by a she-wolf, then raised by a shepherd. When the twins reached adulthood, Romulus founded a city on the Palatine Hill. When Remus jumped over the furrow that marked where the walls would be built, Romulus killed him.

Yet despite the immense popularity of that divinely ordained – if bloodstained – foundation myth, it has no basis in fact. The name Romulus clearly was made up from that of Rome itself, and archaeology has revealed evidence of settlement on the Palatine Hill as early as 1,000 BC.

509 BC: The creation of the Roman Republic

As with the foundation of the city, later Romans believed they knew the precise date of the beginning of the Republic: 509 BC, when the seventh and last king of Rome, the tyrannical Tarquinius Superbus, was thought to have been ousted by an aristocratic coup. Although sources for the early Republic are better than those for the preceding regal period, the veracity of this tale is also in doubt.

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The Republican system itself was based around the idea that only an assembly of the people had the right to pass laws and elect magistrates. The power of the magistrates was limited – they could only hold office for a year, and always had a colleague who could veto any actions. The most senior annual magistrates were the two consuls. In theory the senate, a body made up of serving and ex-magistrates, did no more than offer advice.

There is still lively scholarly debate on the nature of Republican politics in Rome. The traditional view holds that a small number of aristocratic families monopolised the magistracies, and dominated both senate and assemblies. Yet more recently the Republic’s more democratic elements have been emphasised; above all the need for elite politicians to use oratory to persuade assemblies of the people.

338 BC: The settlement of the Latin War

Between 341 and 338 BC the Romans faced a rebellion by their neighbouring Latin allies. After Rome emerged victorious, the settlement they imposed underpinned subsequent Roman conquests of Italy and overseas territories. The Latins, and other Italian allies, were forbidden to conduct diplomacy or enter into treaties with other states. They were not taxed, except in having to provide men to fight in Roman commanded armies, which bolstered their ranks significantly.

It is appealing to think that Roman acquisition of a massive empire was, in large part, a result of the organisation, equipment, and tactical flexibility of its famous legions. Yet, although less glamorous, numbers also played a vital role. The extraordinary levels of manpower that the Roman army could call upon meant that they could suffer crushing defeats in battle, yet still put new men in the field and eventually emerge triumphant.

264–146 BC: The Punic Wars

Rome fought three wars against the great North African city of Carthage. These are known as the Punic Wars, from the Latin name for Carthaginians, Poeni.

The First Punic War (264–241 BC) was fought over control of the island of Sicily, and many of the crucial clashes were naval battles. Rome demonstrated its adaptability in building its first large war fleet, and its almost limitless manpower in building several replacements after repeated catastrophic disasters. Victory gave Rome her initial overseas possession in Sicily.

The Second Punic War (218–201 BC) saw the famous invasion of Italy by Carthaginian general Hannibal. Although Roman resilience and resources were stretched to near breaking point by a string of defeats, Rome ultimately emerged victorious, and the war marked the end of Carthage as a regional power.

The Third Punic War (149–146 BC) was a foregone conclusion, in which Rome was finally successful in destroying its hated rival.

The Punic Wars left Rome as the dominant power in the western Mediterranean. Later Romans looked back on the wars with mixed feelings. On the one hand, the conflicts were glorified as Rome’s finest hour, especially the refusal to submit after Hannibal`s shattering victory at Cannae in 216 BC. Others, though, saw the elimination of Carthage, the only credible threat to Roman existence, as the ushering in of an age of luxury and moral decline.

The second and first centuries BC: the Hellenisation of Rome

During the last two centuries BC, Rome conquered the Eastern Mediterranean by defeating the Hellenistic [ancient Greek] kingdoms founded by the successors of Alexander the Great. These conquests had profound implications for Roman society.

Rome’s relationship with Greek culture was different from that of any other people incorporated into its empire. From the start Romans recognised that Greek culture was both older and more sophisticated than their own. The Roman upper classes embraced Greek literature and philosophy, art and architecture, and by the last century BC it was necessary to be thoroughly conversant with Greek culture to be accepted as a member of the Roman elite. Young boys from rich Roman families learned Greek alongside Latin.

Yet a deep ambiguity remained around these borrowings from a conquered people. Greek culture could be seen as undermining the very manliness of the Romans. As late as the second century AD, the emperor Hadrian was derided as a Graeculus (a 'little Greek') for what some saw as his excessive interest in Greek culture.

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67–62 BC: Pompey in the East

Although far less well known than Caesar’s conquest of Gaul (58–51 BC), the exploits of Pompey in the eastern Mediterranean were more significant in the expansion of Rome. Pompey initially went to the east in 67 BC as part of his campaign against pirates who were infesting the Mediterranean. Having crushed the pirates in just three months, in 66 BC Pompey succeeded to the command against the long-term enemy of Rome, Mithradates VI of Pontus. Again quickly victorious, Pompey then became the first Roman to lead an army to the Euphrates river.

In his so-called ‘settlement of the east’ (a modern term which obscures the expansionist nature of his activities), Pompey established two new Roman provinces (Syria and Bithynia-Pontus), vastly expanded a third (Cilicia), and conducted diplomacy that turned numerous local rulers into clients of Rome. It has been estimated that his ‘settlement’ more than doubled the annual income of the Roman empire.

31 BC–AD 14: Augustus reintroduces monarchy to Rome

The expansion of the empire destroyed the Roman Republic. Institutions designed for a small city-state could not rule a world empire. Above all, vast military campaigns required generals who commanded armies over wide territories for several years. By the last century BC, these generals would lead their armies against Rome and each other.

After a welter of civil wars, Augustus emerged the victor, boasting that he had restored the Republic. However, with overriding military authority and the right to make law, he had in effect reintroduced one-man rule, and become Rome’s first emperor. Augustus spent years experimenting with his constitutional position – his aim was neither to ‘hide’ his sole rule, nor to create a joint rule between himself and the senate, but to find a blend of offices and powers that would allow the touchy pride of Roman senators to serve his new regime. The balance he hit upon has to be considered one of the most successful political settlements in history, as it remained the legal basis of every emperor’s reign for three centuries.

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AD 235–284: the third century crisis

In the 50 years between AD 235 and 284, the Roman empire suffered chronic political and military instability. Amid endemic civil wars and defeats at the hands of barbarians, emperors came and went with bewildering rapidity. The average reign was no more than 18 months, and many survived for much shorter periods.

Three factors brought about the crisis. In the east, repeated Roman attacks had undermined the Arsacid dynasty of Parthia, who were consequently overthrown by the far more aggressive power of the Sassanid Persians. In the north, beyond the Rhine and the Danube, Roman trade and diplomacy had encouraged the formation of large and dangerous barbarian confederations, including the Franks, Alamanni, and Goths.

The final factor was the monopolisation of military glory by the emperor. A major war called for an emperor. If the emperor could not or would not campaign in person on a frontier and one of his generals was successful, the latter would sometimes be proclaimed emperor by his troops, perhaps even against his will. The resulting civil war stripped troops from the frontier, encouraging further barbarian attacks, and opening up the possibility of another local commander being elevated to claim the throne. This vicious circle was finally halted, and the empire given breathing space, by the emperor Diocletian (r284–305). He created the tetrarchy: a ‘college’ of four rulers, one for each of the major frontiers, and one in reserve.

AD 312: Constantine converts to Christianity

At the battle of the Milvian Bridge in AD 312, the emperor Constantine sent his troops into combat with crosses painted on their shields. By the end of his life, he claimed that before the battle he had experienced a vision in which he was given the divine command: “in this sign conquer”. Constantine’s conversion to Christianity had a profound effect on European, and world, history.

Although Christianity was still a minority religion in the reign of Constantine, two events in the third-century crisis had brought the faith into unexpected prominence. Christians had been persecuted from the earliest days of the religion. Yet, with the exception of Nero seeking scapegoats for the great fire of Rome in AD 64, emperors had not sponsored this persecution.

In AD 249, in the face of mounting troubles and seeking to restore divine favour to Rome, the emperor Decius ordered all his subjects to sacrifice to the pagan gods. Later, in AD 257 and 258 the emperor Valerian issued edicts explicitly commanding Christians to return to the traditional gods. The fate of these two imperial persecutors gave a huge boost to Christianity.

Fighting the Goths in AD 250, Decius became the first Roman emperor to die in battle against the barbarians. In AD 260, Valerian was captured alive by the Sassanid Persians, the only emperor ever to suffer such a misfortune. Christians exulted in the vengeance taken by their God, and pagans were given reason to think about the power of the deity of this previously obscure sect.

AD 410: The fall of Rome

In AD 410 the Goths sacked the city of Rome. Sixty-six years later Romulus Augustulus (the ‘Little Emperor’) was deposed, and the Roman empire in the west was at an end.

It has been estimated that more than 200 modern explanations have been put forward to explain the fall of Rome. These range from the rise of Christian monks and clergy (so many unproductive mouths to feed) to impotence brought on by too many hot baths.

In recent times, some scholars have argued that Rome’s collapse was a process of accommodation and compromise between the Romans and the various barbarian peoples. Others, more convincingly, have reiterated the violence, destruction and horror of its downfall. Such vibrant debates underpin the perennial fascination of this world-changing event.

Harry Sidebottom is a lecturer in ancient history at Lincoln College, Oxford, and author of the Warrior of Rome and Throne of the Caesars series of novels.

This article was first published by HistoryExtra in November 2016.