 From Bononia they crossed the Channel to Britain and made their way to Eboracum ( York ) , capital of the province of Britannia Secunda and home to a large military base . Constantine was able to spend a year in northern Britain at his father 's side , campaigning against the Picts beyond Hadrian 's Wall in the summer and autumn . Constantius 's campaign , like that of Septimius Severus before it , probably advanced far into the north without achieving great success . Constantius had become severely sick over the course of his reign , and died on 25 July 306 in Eboracum ( York ) . Before dying , he declared his support for raising Constantine to the rank of full Augustus . The Alamannic king Chrocus , a barbarian taken into service under Constantius , then proclaimed Constantine as Augustus . The troops loyal to Constantius ' memory followed him in acclamation . Gaul and Britain quickly accepted his rule ; Iberia , which had been in his father 's domain for less than a year , rejected it . 
