Constantine I [g] (27 February c. 272 – 22 May 337), also known as Constantine the Great, was a Roman emperor from AD 306 to 337 and the first emperor to convert to Christianity.

Constantine I, aka Constantine the Great, was Roman emperor from 306 to 337 CE. Realizing that the Roman Empire was too large for one man to adequately rule, Emperor Diocletian (284-305 CE) split the empire into two, creating a tetrachy or rule of four.

Constantine the Great was a Roman Emperor from 306 to 337 AD. He was also known as Constantine I or Saint Constantine, in the Orthodox Church as Saint Constantine the Great, Apostolic Equivalent. As an emperor, Constantine carried out many reforms in the administrative, financial, social, and military fields to counter the police.

Constantine the Great (27 Feb c. 272/273 – 22 May 337) Constantine was Roman Emperor (A.D. 306-337). He was the first Roman Emperor to convert to Christianity and played a crucial role in the spread of the religion. With co-Emperor Licinius, he issued the Edict of Milan in 313, which proclaimed tolerance of all religions throughout the empire.