Emperor Constantine the Great, the first Christian emperor in Ancient Rome
Constantine was the first Christian emperor in ancient Rome. He made a great many changes. He made Christianity legal. Under his leadership, people could no longer be arrested just for being Christian. He took the treasures from the temples in Rome and used this wealth to pay for the construction of new Christian churches. He outlawed gladiator contests.
He is famous building the city that carried his name – Constantinople. (This name was later changed to Istanbul.)