Severan periodHadrian's Wall, Brampton, UK
The Roman frontier became Hadrian's Wall again, although Roman incursions into Scotland continued. Initially, outpost forts were occupied in the south-west and Trimontium remained in use but they too were abandoned after the mid-180s. Roman troops, however, penetrated far into the north of modern Scotland several more times. Indeed, there is a greater density of Roman marching camps in Scotland than anywhere else in Europe, as a result of at least four major attempts to subdue the area. The Antonine Wall was occupied again for a brief period after AD 197. The most notable invasion was in 209 when the emperor Septimius Severus, claiming to be provoked by the belligerence of the Maeatae, campaigned against the Caledonian Confederacy. Severus invaded Caledonia with an army perhaps over 40,000 strong. According to Dio Cassius, he inflicted genocidal depredations on the natives and incurred the loss of 50,000 of his own men to the attrition of guerrilla tactics, although it is likely that these figures are a significant exaggeration.
By 210, Severus' campaigning had made significant gains, but his campaign was cut short when he fell fatally ill, dying at Eboracum in 211. Although his son Caracalla continued campaigning the following year, he soon settled for peace. The Romans never campaigned deep into Caledonia again: they soon withdrew south permanently to Hadrian's Wall. From the time of Caracalla onwards, no further attempts were made to permanently occupy territory in Scotland.