A native of Illyricum, Constantius I’s family background is likely to have been relatively humble, despite his son Constantine later claiming that Constantius (c. 250–306 CE) was descended from the emperor Claudius Gothicus (268–270 CE). He rose to prominence through military service and was eventually appointed Caesar (junior emperor) in 293 CE, as part of the arrangement conventionally referred to as the Tetrarchy, comprising the two Augusti (senior emp…