The Second Phase: Vespasian’s Campaign in the Southwest

From an invasion to a wider conquest

The Roman victories of AD 43 and the surrender of rulers in south-east Britain did not mean that the whole island had been conquered. Claudius returned to Rome, while his army continued the work of extending Roman control. Aulus Plautius remained in overall command, and Caratacus had escaped westwards to continue resisting the Romans.

This second phase therefore involved more than following up a single victory. Roman forces had to overcome further communities and secure territory beyond the initial invasion area. Expansion and consolidation went together: capturing land was not the same as keeping control of it.

Vespasian and the Second Legion

Vespasian, who would later become emperor, commanded Legio II Augusta, the Second Legion. During the years following the invasion, he took his forces westwards. His campaign is traditionally associated with southern and south-western Britain.

Suetonius credits Vespasian’s forces with fighting thirty battles, capturing twenty oppida and taking the Isle of Wight. An oppidum was a fortified settlement, often an important centre of local power. Capturing these settlements helped the Romans overcome resistance by taking strongholds rather than merely passing through the countryside.

The number of battles suggests repeated fighting, not one decisive encounter that immediately settled the conquest. The capture of the Isle of Wight also shows that the campaign included an island off Britain’s southern coast as well as advances on the mainland. Together, these achievements give a concrete sense of the scale of Vespasian’s operations.

How certain is the campaign’s route?

The broad picture is a westward advance, but its precise route is less secure. The Isle of Wight is the only geographical location named in Suetonius’ summary of these achievements. Historians have therefore combined the literary account with archaeological evidence to reconstruct a campaign in the south and west.

Roman forces eventually reached at least as far as Exeter, which became a base for II Augusta in the AD 50s. However, the later establishment of a legionary base should not be treated as proof that every stage of Vespasian’s march can be dated or traced exactly. Archaeology helps establish Roman military occupation, but it does not always identify the commander responsible for a particular site.

The Fosse Way and the extent of Roman control

Expansion was not confined to Vespasian’s campaign. Roman forces also advanced northwards towards Lincoln. By AD 47, Roman control probably extended broadly over the territory south and east of a line between the Humber and the Severn estuary.

The alignment of the Roman road called the Fosse Way broadly followed this line. This has led historians to suggest that it served as a convenient frontier during the early occupation. A road along the edge of controlled territory could help soldiers move between positions and support the army’s ability to hold its gains.

However, an early frontier was not necessarily a sharp boundary like a modern national border. Roman control could vary from place to place, and the Fosse Way’s exact role remains debated. It is best understood as a useful indication of the broad extent of the early conquest, rather than an unquestionable dividing line.

What the second phase achieved

Vespasian’s campaign helped turn the initial foothold in the south-east into a much wider occupation. Fighting, the capture of fortified settlements and the development of military bases extended and strengthened Roman power. By AD 47, the Romans controlled a substantial area of Britain, but resistance beyond it continued. The conquest remained an unfinished process.

Vespasian’s campaign

• After AD 43: conquest continued after Claudius returned to Rome; Plautius remained in overall command.
• Vespasian: commanded II Augusta and advanced westwards, traditionally through southern and south-western Britain.
• Suetonius’ account: thirty battles, twenty oppida captured and the Isle of Wight taken.
• The exact route is uncertain; the Isle of Wight is the only location named in this summary.
• Exeter later became a base for II Augusta in the AD 50s.

The Fosse Way

• By AD 47: Roman control broadly extended south and east of the Humber–Severn estuary line.
• The Fosse Way broadly followed this alignment: possibly an early frontier and useful for military movement.
• Its frontier role is debated; it was not a precisely fixed border.

Overall: expansion widened Roman occupation, while consolidation helped secure it. Britain’s conquest was not complete.