Caesar was a politician and general of the late Roman republic, who greatly extended the Roman empire before seizing power and making himself dictator of Rome, paving the way for the imperial system. Caesar as master of Rome and made himself consul and dictator. He used his power to carry out much-needed reform, relieving debt, enlarging the senate, building the Forum Iulium and revising the calendar. Dictatorship was always regarded a temporary position but in 44 BC, Caesar took it for life. His success and ambition alienated strongly republican senators. A group of these, led by Cassius and Brutus, assassinated Caesar on the Ides (15) of March 44 BC. This sparked the final round of civil wars that ended the Republic and brought about the elevation of Caesar's great nephew and designated heir, Octavian, as Augustus, the first emperor.