Severus travelled to Britain in 208, strengthening Hadrian's Wall and reoccupying the Antonine Wall. In AD 209 he invaded Caledonia (modern Scotland) with an army of 50,000 men but his ambitions were cut short when he fell fatally ill of an infectious disease in late 210. He died in early 211 at Eboracum (today York, England), and was succeeded by his sons, who were advised by their mother and his powerful wife Julia Domna, thus founding the Severan dynasty. It was the last dynasty of the Roman Empire before the Crisis of the Third Century.