The Roman Empire was a large autocratic empire (One ruler with supreme power) with large holdings of land in Europe and around the Mediterranean, which succeeded the former Roman Republic with the rise of Augustus in 27 BC. The empire's territorial peak was under the reign of Trajan, but the extent of the land holdings were relatively the same until the end of Constantine the Great's reign, for shortly after conflicts broke out between different populations about religion, and the empire was split into the Western Roman Empire, the Eastern Roman Empire and the Southern Roman Empire. The capital of the Empire was always the founding city of Rome, until Constantine the Great changed the capital to Constantinople, but the change didn't last long, as the Empire split soon after Constantine's d