The divine power of the Pontifex Maximus in ancient Rome

Roman tradition claimed that Numa Pompilius was the second king of Rome and had created the position of Pontifex Maximus in the 7th century BCE, which was part of an effort to organise religious practice.

According to Livy and Plutarch, Numa was traditionally said to have ruled from 715 to 673 BCE and had appointed Numa Marcius as the first man to serve as pontifex.

Although the exact origin of the specific title 'Pontifex Maximus' remains uncertain, later Roman sources applied it later to this early figure, which gave him control over the newly established College of Pontiffs, which included priests responsible for regulating public ritual and sacred law, together with oversight of the calendar.

This religious hierarchy became central to Rome’s identity, and its earliest duties were generally to supervise sacrificial rites and divination rituals and to care for temples and sacred objects. 

After the overthrow of the monarchy in 509 BCE, the Roman Republic retained the College of Pontiffs and continued to appoint a Pontifex Maximus, who remained responsible for interpreting divine law and determining which rites could be lawfully performed.

Over time, the College expanded in size and influence, eventually increasing to fifteen members by the early 1st century BCE during the time of Sulla, though the Pontifex Maximus largely retained overall authority.

Because he also supervised other priestly colleges such as the augurs, who interpreted omens through the flight of birds, and the quindecimviri sacris faciundis, who guarded and consulted the Sibylline Books, his role was incredibly important. 

As Roman society evolved, the functions of the Pontifex Maximus generally expanded into areas previously handled by kings, including the interpretation of omens, the approval of new cults, and the oversight of religious morality.

As a result, he became essential to many decisions that touched nearly every part of Roman public life. 

The Pontifex Maximus largely controlled the fasti, which were official calendars that dictated which days permitted legal business and which required rest and observance of religious rites.

By regulating these public calendars, he could influence civic procedures, electoral meetings, and legal courts, which gave him indirect but considerable power over state affairs.

He also maintained the annales maximi, a set of annual records that documented important political, military, and religious events, which generally provided the Roman people with a sacred narrative of their city’s history. 

More importantly, he interpreted the ius divinum, a body of sacred law that governed all formal interaction with the gods.

This included the approval of construction on religious sites, the offering of state-sponsored sacrifices, and the regulation of religious offices.

In times of natural disaster or military defeat, the Senate often turned to the Pontifex Maximus to determine which ceremonies were required to restore the favour of the gods, and often his rulings carried binding effect.

He could declare certain days as unfavourable or demand that temples be purified, and often his rulings were accepted without challenge. 

He also exercised significant power over the Vestal Virgins, who maintained the eternal flame of Vesta and symbolised Rome’s survival.

Specifically, the Pontifex Maximus selected these priestesses, instructed them in their duties, and punished them when they broke their vows.

Since they were generally considered vital to Rome’s spiritual protection, their obedience to his authority represented his importance in religious matters.

For example, under the emperor Domitian, the Vestal Cornelia was condemned to death in 90 CE because she violated her vow of chastity.

At the same time, he evaluated foreign cults and determined whether new deities could be officially worshipped in Rome.

When the Senate considered adopting the worship of Cybele during the Second Punic War, it consulted the Sibylline Books, a collection of Greek prophetic texts, and the College of Pontiffs to ensure compatibility with Roman practices.

And since the Pontifex Maximus controlled the College, he largely influenced the way foreign religions were integrated and ensured that new beliefs did not challenge Roman traditions. 

At first, the College of Pontiffs usually nominated one of its members, and the Senate ratified the choice.

Because the office had been restricted to patricians, only a small number of elite families competed for the role.

However, this system changed in 104 BCE when Gaius Domitius Ahenobarbus passed the Lex Domitia de Sacerdotiis, which transferred the election to the comitia tributa, a tribal assembly made up of Roman citizens.

As a result, the office became subject to public vote, although only candidates from elite families could stand for election, which largely allowed political contenders to compete directly for religious authority. 

In 63 BCE, Julius Caesar ran for the position against two senior patricians that included Quintus Lutatius Catulus, and borrowed enormous sums, possibly up to 25 million sesterces, to fund his campaign.

He won the election and obtained status and legal protection from prosecution, since the office lasted for life, and he used the office to build support during his rise to power largely because of this protection and his influence over public religion.

After the death of Marcus Aemilius Lepidus in 12 BCE, Augustus took the title for himself and merged it with the powers of the emperor, so that from that point onward every Roman emperor held the position automatically.

This merging of political and religious authority gave the emperor legitimacy in both spheres and largely reinforced the idea that imperial power had divine approval. 

After the Western Roman Empire fell in 476 CE, the bishop of Rome eventually assumed many of the symbolic roles that were once associated with the imperial Pontifex Maximus, although the title itself had not been formally transferred by the emperors.

By the time Pope Leo I served from 440 to 461 CE, the pope had largely taken on the role of spiritual guide and chief moral authority for the city.

Since few other institutions remained functional, the Church became the centre of public life. 

Over time, the term pontifex began to appear in Church documents as a way to describe bishops, especially those with major religious responsibility.

Since the pope presided over the city of Rome and claimed apostolic succession from Saint Peter, he adopted the full title of Pontifex Maximus to express his authority, and when the papacy claimed the title, it connected itself to the ancient traditions of the city and largely reinforced its status as the highest spiritual authority in the Latin-speaking world. 

Eventually, the abbreviation “P.M.” became standard on papal inscriptions, documents, and coins, including coins that Pope Leo X and his successors issued.

While the office no longer involved sacrifices or augury, the title generally preserved the connection to Rome’s sacred past, and today the pope uses the title to signify his role as supreme pontiff and to continue a tradition that began over two thousand years ago with Rome’s earliest kings and their divine guardianship of the city.