Gallus was one of the few who escaped the family massacre initiated by Constantine's sons in order to weed out possible future contestants to the throne. When Constantius II was unable to deal with lesser rebellions out east because more pressing issues required his presence elsewhere, he decided it would be served best if a family member was given the task. So he summoned Gallus, made him Caesar and sent him on his mission. Although he was successful in dealing with the revolts, his methods were found to be so cruel that they would likely spawn new revolts. Word of his heavy-handed manners reached Constantius and he had him recalled. Being led to believe that he was going to be promoted to full Augustus, the happy Gallus arrived at court only to find out he was under arrest. He was then sent to an island, tried and executed.