A state religion is a religious belief system that is officially endorsed and supported by a government. In countries with a state religion, the government may promote the religion through laws, education, and public ceremonies. This can influence the culture and identity of the nation, often intertwining with national symbols and traditions. While some nations have a state religion, others maintain a separation between religion and government. Countries like Saudi Arabia and Iran have Islam as their state religion, while Vatican City is an example of a theocratic state where the Catholic Church plays a central role in governance.