ANSWER: Constantine the Great!

Constantine (306-337 A.D.) was Roman Emperor. It was during the Great Persecution that Constantine had a vision of the sign of Christ on the eve of battle against Emperor Maxentius. Constantine was directed by the dream to place the sign of Christ on the shields of his soldiers. The battle was won.  Christianity would henceforth be practiced freely in the empire.


Vision of the Cross    Room of Constantine   Constantine the Great