Shah Mohammad Reza Pahlavi was the last monarch of Iran, ruling from 1941 until the Iranian Revolution in 1979. He was known for his efforts to modernize Iran through his "White Revolution," which included land reforms, women's rights reforms, and industrialization. He strengthened Iran's military and aimed to create a more centralized state. However, his regime faced increasing opposition, particularly due to political repression and inequality, leading to the 1979 revolution. Despite his accomplishments in modernizing Iran, his reign ended with his exile and the establishment of the Islamic Republic.