55 - Julius Caesar's first invasion of Britain.
54 - Julius Caesar's second invasion of Britain. British forces led, this time, by Cassivellaunus, a capable commander. Despite early Roman advances, British continued to harass the invaders, effectively. A "deal" with the Trinovantes (tribal enemies of Cassivellaunus), and the subsequent desertion of other British tribes, finally guaranteed the Roman victory. Caesar's first two expeditions to Britain were only exploratory in nature, and were never intended to absorb Britain into the Roman sphere, at that time.
54 BC-43 AD - Roman influence manages to increase in Britain during this time, eventhough Roman troops are absent, as a direct result of trade and other interaction with the continent.
AD
5 - Rome acknowledges Cymbeline, King of the Catuvellauni, as king of Britain
43 - Romans, under Aulus Plautius, land at Richborough (Kent) for a full-scale invasion of the island. In the south-east of Britain, Togodumnus and Caratacus have been whipping up anti-Roman feeling and have cut off tribute payments to Rome. Caratacus leads main British resistance to the invasion, but is finally defeated in 51.
51 - Caratacus, British resistance leader, is captured and taken to Rome
61 - Boudicca, queen of the Iceni, led uprising against the Roman occupiers, but is defeated and killed by the Roman governor, Suetonius Paulinus
63 - Joseph of Arimathea came to Glastonbury on the first Christian mission to Britain.
c.75-77 - The Roman conquest of Britain is complete, as Wales is finally subdued; Julius Agricola is imperial governor (to 84)
122 - Construction of Hadrian's Wall ordered along the northern frontier, for the purpose of hindering incursions of the aggressive tribes there into Britannia
133 - Julius Severus, governor of Britain, is sent to Palestine to crush the revolt
138 - When Hadrian died in 138 AD his successor Antonius Pius abandoned the newly completed wall and again pushed northwards.
A new frontier, the Antonine Wall was established between the Forth and Clyde rivers in Scotland.
160 - The Antonine Wall was abandoned and thereafter Hadrian's Wall again became the northern boundary of the Roman Empire in Britain.
167 - At the request of King Lucius, the missionaries, Phagan and Deruvian,were said to have been sent by Pope Eleutherius to convert the Britons to Christianity. This is, perhaps, the most widely believed of the legends of the founding of Christianity in Britain.
184 - Lucius Artorius Castus, commander of a detachment of Sarmatian conscripts stationed in Britain, led his troops to Gaul to quell a rebellion. This is the first appearance of the name, Artorius, in history and some believe that this Roman military man is the original, or basis, for the Arthurian legend. The theory says that Castus' exploits in Gaul, at the head of a contingent of mounted troops, are the basis for later, similar traditions about "King Arthur," and, further, that the name "Artorius" became a title, or honorific, which was ascribed to a famous warrior in the fifth century.
197 - Clodius Albinus, governor of Britain, another claimant to the Imperial throne, is killed by Severus at the battle of Lyon
208 - Severus goes to defend Britain, and repairs Hadrian's Wall
209 - St. Alban, first British martyr, was killed for his faith in one of the few persecutions of Christians ever to take place on the island, during the governorship of Gaius Junius Faustinus Postumianus (there is controversy about the date of Alban's martyrdom. Some believe it occurred during the persecutions of Diocletian, in the next century, although we opt for the earlier dating).
c.270 - Beginning (highly uncertain dating) of the "Saxon Shore" fort system, a chain of coastal forts in the south and east of Britain, listed in a document known as "Notitia Dignitatum."
287 - Revolt by Carausius, commander of the Roman British fleet, who rules Britain as emperor until murdered by Allectus, a fellow rebel, in 293
303 - Diocletian orders a general persecution of the Christians
306 - Constantine (later to be known as "the Great") was proclaimed Emperor at York.
311 - Persecution of Christians in the Roman Empire ends.
312 - Constantine defeats and kills Maxentius at battle of Milvian Bridge; Constantine realizes Christian God may be a powerful ally and decides to attempt to co-opt him for his own purposes.
313 - Edict of Toleration proclaimed at Milan, in which Christianity is made legal throughout the empire.
314 - Three British bishops, for the first time, attend a continental church gathering, the Council of Arles.
324 - Constantine finally achieves full control over an undivided empire. He was a skillful politician who is popularly believed to have made Christianity the official religion of the empire because of his personal convictions. In actuality, that act was merely an expedient intended to harness the power of its "God" for the benefit of the state. He re-located the imperial headquarters to Byzantium, whose name he then changed to Constantinople.
Despite his outward enthusiasm for Christianity and its powerful God, he didn't close many pagan temples during his reign. He did, however, strip them of their former wealth, which was then shifted to various Christian churches. This produced the result that many of the fledgling churches were put on a very firm financial footing and many of their members enjoyed great prosperity. The persecution of Christianity had stopped, perhaps, but its co-opting had just begun.
Early Christianity had no official hierarchies and functioned best as a series of small church groups worshipping with and caring for their own members while spreading the Gospel in their local areas. Constantine's move created a top-heavy structure that would quickly depart from its original purity; a church beholden to the state, out of touch with the needs of its adherents and concerned only with its own comfort. Eusebius, the early Christian historian, has given us some additional insights into the motivations of the Emperor Constantine in his "Ecclesiastical History"
337 - Constantine received "Christian" baptism on his deathbed. Joint rule of Constantine's three sons: Constantine II (to 340); Constans (to 350); Constantius (to 361)
360's - Series of attacks on Britain from the north by the Picts, the Attacotti and the Irish (Scots), requiring the intervention of Roman generals leading special legions.
369 - Roman general Theodosius drives the Picts and Scots out of Roman Britain
383 - Magnus Maximus (Macsen Wledig), a Spaniard, was proclaimed Emperor in Britain by the island's Roman garrison. With an army of British volunteers, he quickly conquered Gaul, Spain and Italy.
388 - Maximus occupied Rome itself. Theodosius, the eastern Emperor, defeated him in battle and beheaded him in July, 388, with many of the remnant of Maximus' troops settling in Armorica. The net result to Britain was the loss of many valuable troops needed for the island's defense (the "first migration").
395 - Theodosius, the last emperor to rule an undivided empire, died, leaving his one son, Arcadius, emperor in the East and his other son, the young Honorius, emperor in the West. At this point the office of Roman Emperor changed from a position of absolute power to one of being merely a head of state.
396 - The Roman general, Stilicho, acting as regent in the western empire during Honorius' minority, reorganized British defenses decimated by the Magnus Maximus debacle. Began transfer of military authority from Roman commanders to local British chieftains.
397 - The Roman commander, Stilicho, comes to Britain and repels an attack by Picts, Irish and Saxons.
402 - Events on the continent force Stilicho to recall one of the two British legions to assist with the defense of Italy against Alaric and the Visigoths. The recalled legion, known as the Sixth Victrix, was said by Claudian (in "De Bello Gallico," 416) to be "that legion which is stretched before the remoter Britons, which curbs the Scot, and gazes on the tattoo-marks on the pale face of the dying Pict." The barbarians were defeated, this time, at battle of Pollentia.
403 - Victricius, Bishop of Rouen, visited Britain for the purpose of bringing peace to the island's clergy, who were in the midst of a dispute, possibly over the Pelagian heresy.
405 - The British troops, which had been recalled to assist Stilicho, were never returned to Britain as they had to stay in Italy to fight off another, deeper penetration by the barbarian chieftain, Radagaisus.
406 - In early January, 406, a combined barbarian force (Suevi, Alans, Vandals & Burgundians) swept into central Gaul, severing contact between Rome and Britain. In autumn 406, the remaining Roman army in Britain decided to mutiny. One Marcus was proclaimed emperor in Britain, but was immediately assassinated.
407 - In place of the assassinated Marcus, Gratian was elevated "to the purple," but lasted only four months. Constantine III was hailed as the new emperor by Roman garrison in Britian. He proceeded to follow the example of Magnus Maximus by withdrawing the remaining Roman legion, the Second Augusta, and crossing over into Gaul to rally support for his cause. Constantine's departure could be what Nennius called "the end of the Roman Empire in Britain. . ."
408 - With both Roman legions withdrawn, Britain endures devastating attacks by the Picts, Scots and Saxons.
409 - Prosper, in his chronicle, says, "in the fifteenth year of Honorius and Arcadius (409), on account of the languishing state of the Romans, the strength of the Britons was brought to a desperate pass." Under enormous pressure, Britons take matters into their own hands, expelling weak Roman officials and fighting for themselves.
410 - Britain gains "independence" from Rome. The Goths, under Alaric, sack Rome.
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