The victory of the followers of Constantine over the army of Maxentius at the Battle of Milvian Bridge occurred on this date A.D. 312.



. . . Accordingly he called on God with earnest prayer and supplications that He would reveal to him Who He was, and stretch forth his right hand to help him in his present difficulties. And while he was thus praying with fervent entreaty, a most marvelous sign appeared to him from heaven, the account of which it might have been hard to believe, had it been related by any other person. But since the Victorious Emperor himself long afterwards declared it to the writer of this History, when he was honored with his acquaintance and society, and confirmed his statement with an oath, who could not believe the account especially since subsequent events established its truth?



He said that about noon, when the day was already beginning to decline, he saw with his own eyes the trophy of a cross of light in the heavens, above the sun, bearing the inscription IN HOC SIGNO VINCES. At this sight, he himself was struck with amazement, and his whole army which was with him on this expedition too and which witnessed this miracle.





"He said that he doubted within himself what importance the vision might hold. He continued to ponder its meaning through until he fell asleep. While sleeping, the Christ of God appeared to him with the same sign he had seen earlier in the heavens. God commanded him to make a likeness of that sign which he had seen in the heavens and to use it as a safeguard in all encounters with his enemies."



Eusebius of Caesarea, Life of Constantine, 28.