Final answer:
Julius Caesar gave himself the title of 'dictator perpetuo,' a move that broke from the traditional six-month term limit for dictators in the Roman Republic and contributed to his assassination; later, Augustus established himself as 'Princeps Civitatus' to avoid monarchical implications while holding power.
Step-by-step explanation:
The title Julius Caesar gave himself after bypassing the six-month limit was dictator perpetuo, meaning 'dictator in perpetuity' or 'dictator for life'.
Before Caesar, the office of dictator in Roman Republic was conferred only in times of grave crisis and typically lasted for just six months. However, Julius Caesar, a pivotal figure in the transition from Roman Republic to Empire, pushed the boundaries of Roman political tradition. His assumption of the dictatorship for life in 44 BCE was a key moment that led many contemporaries to view him as a tyrannical figure, ultimately contributing to his assassination by his former allies in the Senate, including Brutus and Cassius.
Augustus, Julius Caesar's adopted heir, learned from his predecessor's fate, carefully crafting a new title, Princeps Civitatus, or 'first citizen,' which indicated a more benign leadership role while de facto establishing autocratic rule. This marked the beginning of the Principate, the early phase of the Roman Empire, which gave an illusion of republican governance while the emperor held actual power. Augustus was savvy in utilizing this title to allay fears of tyrannical monarchy that was despised in Roman culture; thus, he started the tradition of the Roman Empire that followed.