What ancient Roman title refers to the priests who were custodians of religious knowledge and texts?

The title that refers to the priests who were custodians of religious knowledge and texts is Quindecemviri. This group was responsible for the care of the Sibylline Books, a collection of prophetic texts that were of great significance in ancient Roman religion. The Quindecemviri had a critical role in interpreting these texts and ensuring that the knowledge contained within them was preserved and used properly for the benefit of the state and its religious practices.

Flamines were priests dedicated to specific gods and did not have the same responsibilities regarding sacred texts. Augures were more focused on interpreting omens from the flight of birds and did not hold the role of custodians of written religious knowledge. Salii were a group of priests associated with the worship of Mars who performed ceremonial dances and rituals, but they were not tasked with maintaining religious texts or knowledge. Thus, the Quindecemviri uniquely fits the description of custodians of religious knowledge and texts.