君士坦提烏斯二世
Constantius II was proclaimed "caesar" in 334, and became Eastern Emperor in 337, after the death of Constantine I. After Constans was killed by the usurper Magnentius, Constantius laid claim to the Western Empire, and after defeating Magnentius in 351, took possession of it, becoming sole emperor. Constantius II died in 361, of a violent fever.