Until 1935, Iran was known as Persia. The Medes and the Persians united in 549 BC to form the Persian Empire. Alexander the Great conquered Persia in 333 BC. Arabs brought Islam to Persia in the 7th century. Turks and Mongols ruled from the 11th century until 1502, when a native dynasty reasserted full independence. Afghanistan was severed from Iran by the British in 1857. Conservative Moslem protests in the late 1970's led to the fall of the government and the exile of Shah Reza Pahlavi. The Islamic Constitution of 1979 put an end to the monarchy, declaring Iran an Islamic Republic, and vesting final authority in the Islamic spiritual leader (then the Ayatollah Khomeini).
War broke out with Iraq on 22 September 1980 over sovereignty of the Shatt al-Arab waterway. Fighting continued until 1988.
The political upheavals, marked by a sometimes brutal fundamentalism, brought Iran to almost total isolation from the rest of the world.
