The legion was probably founded shortly after 31 BC by the emperor
Augustus. XX
Valeria victrix was probably part of the large Roman force that fought in the
Cantabrian Wars in
Hispania from 25 to 19 BC. The legion then moved to
Burnum in
Illyricum at the beginning of the
Great Illyrian revolt (
Bellum Batonianum) in AD 6. It is recorded operating against the
Marcomanni in AD 6 in the army of
Tiberius. In Illyria they were led by the governor of Illyricum,
Marcus Valerius Messalla Messallinus, who may have given his clan (
gens) name
Valeria to the legion. Although understrength, they managed to defeat the rebels led by
Bato of the Daesitiates. In one battle the legion cut through the enemy lines, was surrounded, and cut its way out again. After the disaster of
Varus in AD 9, XX
Valeria Victrix moved to
Germania Inferior and was based at
Oppidum Ubiorum, then moved to Novaesium at the site of modern
Neuss during Tiberius' reign. The legion was one of the four with which
Claudius invaded Britain in 43 AD. It was also one of the legions that defeated
Caratacus at the
Battle of Caer Caradoc, after which, from the AD 50s, it was encamped at
Camulodunum, with a few units at Kingsholm in
Gloucester. Around AD 55 under the command of Manlius Valens it moved to
Usk, in an unsuccessful attempt to
pacify the
Silures, a tribe very resistant to the imposition of Roman rule in Wales. But the legion suffered defeat, resulting in Valens’ replacement as legate In AD 60 or 61 the Twentieth helped put down the revolt of queen
Boudica, after outflanking the
Ordovices it took part in the
second Roman invasion of Anglesey which destroyed the
Celtic Druids and their
religious practices. In AD 66, the legion was transferred to the much more passive
Viroconium (
Wroxeter). It may also have occupied
Gloucester (
Glevum) at this time. , close to
Duntocher. It may have been a "waster" and lacks distance data. It has been scanned and a video produced. '' (now
Chester), a Roman castrum shown in the figure. The Legio was stationed in
Roman Britain until the beginning of the fifth century In the
year of the four emperors, the legion sided with
Vitellius. Some units went with him to
Rome. In AD 78–84, the legion was part of
Gnaeus Julius Agricola's campaigns in northern Britannia and Caledonia, and built the base at
Inchtuthill. In AD 88 the legion returned south and occupied Castra Deva (
Deva Victrix), where it remained based for at least two centuries. The Twentieth was among the legions involved with the construction of
Hadrian's Wall, and the discovery of stone altars commemorating their work in
Caledonia suggests that they had some role in building the
Antonine Wall. The legion probably went on campaign in 196 under
Decimus Clodius Albinus into
Gaul, and would have suffered heavy losses in Gaul before returning to Britain. During the
Carausian Revolt, which established the
Britannic Empire under
Carausius and
Allectus in the 280s and 290s, the XX
Valeria Victrix was still active. No further information is known after this period and scholars believe Legio XX was still stationed in Britain when
Constantine III pulled the bulk of the military forces from there in the year 407 for his doomed campaign on the continent. This legion has been much studied; at least 250 members of the legion have been identified in surviving inscriptions. == Attested members ==