In Hoc Signo Vinces

October 27 and 28

In Hoc Signo Vinces (By this sign you will conquer)

October 28 marks the anniversary of the Battle of the Milvian Bridge (AD 312) at which Constantine the Great defeated the usurper Maxentius who had set himself up as emperor in Rome. Son of the emperor Maximian Herculius, Maxentius claimed the same right to the throne that Constantine had claimed from his own father, the emperor Constantius I Chlorus. The difference was that Constantius conferred the imperial power upon his son Constantine on his deathbed, whereas Maxentius took his father’s authority by force and drove the old man from Rome. (1)

Photo by Beverly Stevens

Constantine had defeated Maxentius’s forces in Turin and Verona, and advanced south, towards the bend of the Tiber River, where the Milvan Bridge crossed it. Maxentius had cut the bridge, and was on the other side in Rome with a superior in numbers force.  It is said that Maxentius trusted a pagan oracle that said “the enemy of Rome would perish.”

But it was October 27 when Constantine looked to the sky, and implored the Deus Summus to help.  According to Lactantius, Constantine had a dream on October 27 in which he saw the Chi and the Rho {The Chi-Ro is a combination of the first two letters of Christ’s name in Greek, which is spelled ΧΡΙΣΤΟΣ (7) }, and heard the words “In Hoc Signo Vinces (By this sign you will conquer).” (3)  

On October 28th, Constantine ordered the ☧ to be painted on all his soldiers’ shields. (7)

Chi Rho

Later, Constantine confided to Bishop Eusebius of Caesarea, and swore an oath what took placed was true.  Constantine said “he saw with his own eyes in the heavens a trophy of the cross arising from the light of the sun, carrying a message, Conquer by This” (Hoc Signo Victor Eris in the original Latin of Constatine, but TOUTO NIKA in the Greek translation of Eusebius). (4)  Constantine also related this information to his family and friends.

The battle of October 28th was what, some say, helped to convert Constantine fully to Christianity.  “Having see the sign, his troops stood to arms. The enemies advanced, but without their emperor, and they crossed the bridge. The armies met, and fought with the utmost exertions of valour, and firmly maintained their ground. In the meantime a sedition arose at Rome, and Maxentius was reviled as one who had abandoned all concern for the safety of the commonweal; and suddenly, while he exhibited the Circensian games on the anniversary of his reign, the people cried with one voice, “Constantine cannot be overcome!” Dismayed at this, Maxentius burst from the assembly, and having called some senators together, ordered the Sibylline books to be searched. In them it was found that:

On the same day the enemy of the Romans should perish.

Led by this response to the hopes of victory, he went to the field. The bridge in his rear was broken down. At sight of that the battle grew hotter. The hand of the Lord prevailed, and the forces of Maxentius were routed. He fled towards the broken bridge; but the multitude pressing on him, he was driven headlong into the Tiber.

This destructive war being ended, Constantine was acknowledged as emperor, with great rejoicings, by the senate and people of Rome. And now he came to know the perfidy of Daia; for he found the letters written to Maxentius, and saw the statues and portraits of the two associates which had been set up together. The senate, in reward of the valour of Constantine, decreed to him the title of Maximus (the Greatest), a title which Daia had always arrogated to himself.  (3)

In 313, one year later, Christianity was legalized, ending 300 years of persecution. Constantine also began to aggressively patronize Christianity, funding Christian building projects, giving special favors to clergy, and allowing Christians to be appointed to positions of power and authority. (7)

Constantine, whose mother was Saint Helen, was on the road to becoming a Christian.  He was baptized on his deathbed, something common in that day.  Under Constantine, Christianity was transformed from a persecuted religion, to an established religion.  As Saint Monica helped bring Saint Augustine to faith with her prayers, we can say the same for Saint Helen with regards to Constantine.  “Some say Constantine stands as a great political and military leader, as well as one of the most influential religious and cultural figures in world history.” (5)


                              Side view of Ponte Milvio, 2005,

Featured Image: Battle of the Milvian Bridge by Giulio Romano, 1520-24 (6)

  4. Eusebius: The Church history. Paul L. Maier.
  5. Constantine and the Christine Empire. Charles Matson Odahl.

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