Ancient Rome was a civilization that started in modern-day Italy, in the 8th Century before Christ. The civilization lasted for 12 centuries. It ended, when Mehmed II conquered Constantinople, on May 29, 1453. According to legend, the Roman civilization was founded by Romulus and Remus, in the year 753 BC. The Roman Empire developed in wars against Carthage and the Seleucid Empire. Julius Caesar conquered Gaul, modern France, and Augustus ended the Roman republic by becoming emperor. At its biggest extent, the empire covered all of the Mediterranean. Rome became so big, because it led war against other nations and then assimilated their culture.