Passage: Initially, Rome was ruled by kings, who were elected from each of Rome's major tribes in turn. The exact nature of the king's power is uncertain. He may have held near-absolute power, or may also have merely been the chief executive of the Senate and the people. At least in military matters, the king's authority (Imperium) was likely absolute. He was also the head of the state religion. In addition to the authority of the King, there were three administrative assemblies: the Senate, which acted as an advisory body for the King; the Comitia Curiata, which could endorse and ratify laws suggested by the King; and the Comitia Calata, which was an assembly of the priestly college that could assemble the people to bear witness to certain acts, hear proclamations, and declare the feast and holiday schedule for the next month.

Question: What was he also in charge of?
the state religion