Constantine the Great

Constantine the Great (c. 272-337 CE) was Roman emperor from 306 to 337, the first Roman emperor to convert to Christianity. After years of civil war against rival claimants, he reunified the empire under his sole rule and, with the Edict of Milan in 313, extended legal toleration to Christianity throughout the empire, ending the era of state persecution. He founded a new eastern capital at Byzantium, renamed Constantinople in his honor, which remained the seat of the Roman and later Byzantine Empire for over a thousand years. He also convened the First Council of Nicaea in 325 to settle a major doctrinal dispute within the early Christian church. His reign marks a decisive turning point in both Roman and Christian history.