Constantine (272-337) was the first Roman emperor to convert to Christianity, after a moment of revelation in the campaign that culminated at the Milvian Bridge.

His opponent was Maxentius, and at the battle of the Milvian Bridge, Constantine claims to have seen a cross emblazoned with the words “By this sign you will conquer” or something to that effect.

Constantine saw the meteor (or the blast) and somehow got a cross out of it and a voice proclaimed, "By this, you shall conquer."<br><br>Hogwarts!<br><br>That plot is as full of holes as the ...

Whether insipid or enchanting, the custom would spread from the Milvian Bridge like teen acne. Love padlocks erupted on historic bridges in Naples, Milan, Florence and Venice.

On July 25th 306 AD, Constantine was proclaimed emperor of Rome, in York. But he had to earn the title, and did so at the Battle of Milvian Bridge, where he defeated a persistent usurper, Maxentius.