Roman religion was a polytheistic system that evolved from Etruscan and Greek influences. It included state-sanctioned practices and the worship of emperors as divine figures. The imperial cult emerged as a tool for political unity and legitimacy. Key concepts include the Pontifex Maximus, augury, and household gods like Lares and Genius. Rituals involved animal sacrifices, libations, and divination. The state religion and imperial cult shaped Roman identity and social hierarchies throughout the empire's history.