Mohammad Reza Shah Pahlavi was the last monarch of Iran, ruling from 1941 until his overthrow in 1979. He was born on October 27, 1919, and became Shah after his father, Reza Shah Pahlavi, was forced to abdicate during World War II. His reign was marked by efforts to modernize and westernize Iran, including economic reforms and the promotion of education. The Shah's rule faced significant opposition, particularly from religious leaders and political groups. His authoritarian approach and close ties with the United States led to widespread discontent. In 1979, he was ousted during the Iranian Revolution, which resulted in the establishment of an Islamic Republic.