Roman Coin - Guaranteed Ancient & Authentic - Constantine I - 307-337 AD (20R59). Shipped with USPS First Class. Constantine I 307-337 A.D. Constantine I, known as "Constantine the Great", was born around 274 A.D. In 306 A.D. he was proclaimed Caesar at the death of his father, Constantius Chlorus. Constantine famously converted to Christianity after a successful battle. He successfully defeated co-emperors Maxentius and Licinius I, thereby becoming sole ruler by 324 A.D. In 327 he succumbed to illness and died shortly thereafter. Reverse reads: GLORIA EXERCITVS "To the glory of the army." Two soldiers standing facing, heads turned inward at two standards between them, each holding a spear.