Gaius Julius Caesar (pronounce [ˈgaːius ˈjuːlius ˈkaɪsar] in Classical Latin; conventionally pronounced /ˈgaɪəs ˈdʒuːliəs ˈsiːzɚ/ in English), July 13, 100 BC – March 15, 44 BC), was a Roman military and political leader. He played a critical role in the transformation of the Roman Republic into the Roman Empire.