The Roman Empire was the post-Republican phase of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and across the Mediterranean. The Roman Republic, which preceded it, had been weakened and subverted through several civil wars.Several events are commonly proposed to mark the transition from Republic to Empire, including Julius Caesar’s appointment as perpetual dictator (44 BC), the Battle of Actium (2 September 31 BC), and the Roman Senate’s granting to Octavian the honorific Augustus (4 January 27 BC). Roman expansion began in the days of the Republic, but reached its zenith under Emperor Trajan. Only at that territorial peak, the Roman Empire controlled approximately 6.5 million km² of land surface. Due to the Empire’s vast extent and long endurance, Roman influence upon the language, religion, architecture, philosophy, law, and government of nations around the world lasts to this day.