In 43 CE, Emperor Claudius authorized a major invasion of Britain, turning earlier Roman contact into a sustained conquest. Aulus Plautius led the initial army, aiming to defeat powerful south-eastern kingdoms and create a new province.
After landing, Roman forces fought key early battles against British leaders linked to the Catuvellauni, helping them break organized resistance in the southeast. These victories opened routes for Roman advance and supply, making further operations inland possible.
Within weeks of the landing, the Romans captured Camulodunum (modern Colchester), which became an early center of Roman power. Claudius’s association with the victory helped present the conquest as an imperial achievement, not just a general’s war.
In 47 CE, Publius Ostorius Scapula replaced the first governor and shifted toward tighter control and expansion. He pushed into Wales and other resistant areas, showing that conquest required years of campaigning beyond the initial takeover of the southeast.
Around 50–51 CE, the resistance leader Caratacus suffered defeat and then sought protection with Queen Cartimandua of the Brigantes. She handed him to the Romans, removing a major symbol of armed opposition and strengthening Rome’s influence through local allies.
By 60–61 CE, Governor Gaius Suetonius Paulinus struck at Mona (Anglesey), described by Roman writers as a refuge for opponents and a stronghold of druids. The campaign aimed to remove a base of resistance in northwest Wales, but events elsewhere forced a sudden shift.
In 60–61 CE, Boudica led an uprising involving the Iceni and allies, attacking major Roman centers including Camulodunum and Londinium. The revolt exposed weaknesses in early Roman rule, especially resentment over harsh administration and loss of local autonomy.
Suetonius Paulinus regrouped forces and defeated the rebels in a decisive battle, ending the immediate crisis. Afterward, Rome adjusted governance and security to reduce the risk of another large-scale rebellion while continuing the wider conquest.
From 71 to 74 CE, Governor Quintus Petillius Cerialis pushed into northern England against the Brigantes, a key power in the region. These operations extended Roman control beyond the earlier southern focus and helped set conditions for later advances toward Scotland.
Sextus Julius Frontinus governed from about 74 to 78 CE and is credited by later tradition with strong progress against resistant Welsh groups, including the Silures. His campaigns tightened Roman control in the west, reducing the number of regions still outside direct rule.
Agricola took office in 77/78 CE and quickly attacked remaining pockets of resistance in Wales, including operations against the Ordovices and renewed action on Mona (Anglesey). This consolidation freed Roman resources for expansion farther north.
Between 79 and 82 CE, Agricola advanced into northern Britain and began sustained campaigning toward Caledonia (modern Scotland). Tacitus describes a strategy of combining force with fort-building to hold ground and pressure local groups into submission.
In 83 CE (sometimes dated 84), Agricola fought the Battle of Mons Graupius, described by Tacitus as a major Roman victory over a Caledonian confederation. Even with battlefield success, long-distance supply and continued resistance made permanent conquest of all Scotland difficult.
Agricola was recalled to Rome after his northern campaigns, ending the most aggressive phase of expansion in Britain during this period. By about 84 CE, Roman control covered most of what is now England and Wales, while the far north remained contested and costly to hold.
Roman Conquest of Britain under Claudius to Agricola (43–84 CE)