Pontifex Maximus

The pontifex maximus headed the College of Pontiffs, the senior body of priests responsible for Rome's state religion, overseeing the calendar, the performance of public sacrifices, the college of Vestal Virgins who tended the sacred fire of Vesta, and the maintenance of the pontifical records that preserved precedent for religious law. Roman tradition attributed the office's founding to Numa Pompilius, the legendary second king of Rome credited with establishing much of the city's early religious institutions, though the office is first solidly attested historically during the early Republic, after the abolition of the monarchy around 509 BCE.

The pontifex maximus was not primarily a mystic or theologian in the sense familiar from many other traditions in this record; Roman state religion was oriented toward correct ritual performance, orthopraxy, as the guarantor of the state's relationship with the gods, the pax deorum or peace of the gods, rather than toward personal belief or revelation. Holding the office therefore carried substantial political as well as religious weight, since control over the religious calendar, including the timing of elections and assemblies, and over which omens were declared favorable or unfavorable, gave the pontifex maximus real influence over the conduct of Roman public life.

For most of the Republic, the pontifex maximus was chosen by co-optation, meaning the existing College of Pontiffs selected new members and its own head from among Rome's elite; a law of 104 BCE, the lex Domitia, shifted selection to election by a specially convened subset of the Roman citizen assembly, a change that opened the office more directly to political competition. Julius Caesar won election as pontifex maximus in 63 BCE, a position he held alongside his subsequent political and military career and which contributed to his religious as well as political authority in the years before his assassination in 44 BCE.

Under the Empire, Augustus took the office himself in 12 BCE, and from that point the title passed automatically to whoever held imperial power, fusing supreme religious and political authority in the person of the emperor for the following four centuries. The office lapsed as a state institution when the Christian emperor Gratian declined the title around 375 to 382 CE, a symbolic break with Rome's traditional state cult as the empire moved toward Christianity as its official religion. The Latin title was later adopted by the Bishop of Rome as one of several papal titles, a deliberate act of appropriated Roman vocabulary rather than any institutional continuity from the pagan Roman priesthood.