The Shah of Iran was the monarch of Iran until the Islamic Revolution of 1979. The title "Shah" means "king" in Persian and was used by Iranian emperors and kings for centuries. Some synonyms for the Shah of Iran include King of Persia, Emperor of Iran, and Monarch of Iran. Other titles that were used by the Shah of Iran include Mohammad Reza Shah Pahlavi and Aryamehr, which means "Light of the Aryans." Despite the different titles, the Shah of Iran was the absolute ruler of Iran and held significant power over his people until he was overthrown in the revolution.