Roman Britain

After capturing the south of the island, the Romans turned their attention to what is now Wales. The Silures, Ordovices and Deceangli remained implacably opposed to the invaders and for the first few decades were the focus of Roman military attention, despite occasional minor revolts among Roman allies like the Brigantes and the Iceni. The Silures were led by Caratacus, and he carried out an effective guerilla campaign against Governor Publius Ostorius Scapula. Finally, in 51 AD, Ostorius lured Caratacus into a set-piece battle and defeated him. The British leader sought refuge among the Brigantes, but their queen, Cartimandua, proved her loyalty by surrendering him to the Romans. He was brought as a captive to Rome, where a dignified speech he made during Claudius's triumph persuaded the emperor to spare his life. However, the Silures were still not pacified, and Cartimandua's ex-husband Venutius replaced Caratacus as the most prominent leader of British resistance.
In 60-61 AD, while Governor Gaius Suetonius Paulinus was campaigning in Wales, the southeast of Britain rose in revolt under the leadership of Boudica. Boudica was the widow of the recently-deceased king of the Iceni, Prasutagus. The Roman historian Tacitus reports that Prasutagus had left a will leaving half his kingdom to Nero in the hope that the remainder would be left untouched. He was wrong. When his will was enforced, Rome responded by violently seizing the tribe's lands in full. Boudica protested. In consequence, Rome punished her and her daughters by flogging and rape. In response, the Iceni, joined by the Trinovantes, destroyed the Roman colony at Camulodunum (Colchester) and routed the part of the IXth legion that was sent to relieve it. Suetonius Paulinus rode to London, the rebels' next target, but concluded it could not be defended. Abandoned, it was destroyed, as was Verulamium (St Albans). Between seventy and eighty thousand people are said to have been killed in the three cities. But Suetonius regrouped with two of the three legions still available to him, chose a battlefield, and, despite being heavily outnumbered, defeated the rebels in the Battle of Watling Street. Boudica died not long afterwards, by self-administered poison or by illness. During this time, the Emperor Nero considered withdrawing Roman forces from Britain altogether.
There was further turmoil in 69 AD, the "year of four emperors". As civil war raged in Rome, weak governors were unable to control the legions in Britain, and Venutius of the Brigantes seized his chance. The Romans had previously defended Cartimandua against him, but this time were unable to do so. Cartimandua was evacuated, and Venutius was left in control of the north of the country. After Vespasian secured the empire, his first two appointments as governor, Quintus Petillius Cerialis and Sextus Julius Frontinus, took on the task of subduing the Brigantes and Silures respectively. Frontinus extended Roman rule to all of South Wales, and initiated exploitation of the mineral resources, such as the gold mines at Dolaucothi.
In the following years, the Romans conquered more of the island, increasing the size of Roman Britain. Governor Gnaeus Julius Agricola, father-in-law to the historian Tacitus, conquered the Ordovices in 78 AD. With the XXth Valeria Victrix legion, Agricola defeated the Caledonians in 84 AD at the Battle of Mons Graupius, in northern Scotland. This was the high water mark of Roman territory in Britain: shortly after his victory, Agricola was recalled from Britain back to Rome, and the Romans retired to a more defensible line along the Forth-Clyde isthmus, freeing soldiers badly needed along other frontiers.
For much of the history of Roman Britain, a large number of soldiers were garrisoned on the island. This required that the emperor station a trusted senior man as governor of the province. As a result, many future emperors served as governors or legates in this province, including Vespasian, Pertinax, and Gordian I.