(1) A Ruler Touched by the Divine: Though ruthless in pursuit of power, Constantine never made Christianity the official religion of the Roman state. (WSJ)

On Oct. 28, 312—17 centuries and a couple months ago—the armies of two rival Roman emperors clashed at the Battle of the Milvian Bridge just outside Rome. One of the leaders was Constantine, and before the battle he ordered his soldiers to paint a symbol made up of the Greek characters chi and rho on their shields, assuring them that it was a sign of divine support.