Vintage Imperial Roman Coin Constantine The Great 306 AD - 337 AD COA ICSVintage Imperial Roman coin of Constantine the Great who ruled from 306 A. D. 337 A. D. Constantine the Great was the son of Constantine Chlorus. Constantine reunited the western and eastern empires into the Roman Empire, and became the sole emperor With his Edict of Milan in 313 A. D., he decreed tolerance for Christianity. He abolished public gladiator fights, and established a new capital at Constantinople Constantine the Great was baptized a