The ancient Olympics stopped because of a ban on pagan festivals by the emperor Theodosius I. Like other Christians, he saw the Olympic Games, which honored the Greek god Zeus, as an offense to his Christian religion.
As Christianity's influence waxed in the Roman Empire, the popularity of the Olympic Games waned. By the 3rd century A.D., lists of the winners of the games became less certain, and the physical infrastructure of the area around Olympia, where the games were held, began to fall apart due to war, earthquakes and floods. In 393 A.D., the emperor Theodosius I issued a decree suppressing all pagan festivals to bolster Rome's state religion, Christianity. This decree officially killed the Olympic Games.