Answer: Emperor's Constantine dream about winning the war againts the Maxentius by the sign of a cross. He changed the religion of the Roman Empire to Christianity, making it the 'official' religion of the Roman State.
Step-by-step explanation:
By the late third century Christians were well established in Rome, and elsewhere in the empire - even though they probably formed only a small minority of the population, and their growth may have been held back by periods of persecution. as the result of a dream, Constantine had inscribed 'the heavenly sign of God' on his soldiers' shields just before the decisive conflict against Maxentius outside the city at the Battle of MiKaan Bridge. Constantine abandoned traditional divinities of Rome in favor of the Christian gods, making this one of the most controversial and unexpected events in Roman history.