Iran, historically known as Persia, is located in Western Asia. In 1935, Reza Shah Pahlavi officially changed the country's name to Iran. Iran has over 2,500 years of history and was home to several ancient empires and dynasties. In 1979, the Islamic Revolution transformed Iran from a monarchy to an Islamic republic led by Ayatollah Khomeini. Today, Iran has a population of nearly 70 million people, most of whom are Shi'a Muslims, and has a mixed economy dominated by oil and gas exports.