Persia was the most extensive of the ancient empires and controlled its territory, although with declining power from the mid-400's, until it was conquered by Alexander the Great in 331 B.C. Religion During its long history, Iran has been invaded and controlled by many different foreign powers. Perhaps the most important invasion was in the mid-600's A.D. when Muslim Arabs conquered the country. About 99 percent of the Iranian people today are Muslims with Christians making up only a small percent of the population. The official language of Iran is Persian, also called Farsi, and belongs to the Indo-European family of languages. Almost all the people speak it, either as their native tongue or as a second language, but only about 48 percent of the people over the age of 15 can read and write.
Schools teach in Farsi, and government agencies communicate in it.
The present language, written in Arabic script, has borrowed many words from the Arabic language. Changes At the turn of the 20th century, oil was discovered, and the British corporation, the Anglo-Persian Oil Company, began its development. This would alter Iran's economy and world influence. About the same time Iranian intellectuals and others who had been influenced by new ideas of political freedom began to demand a constitutional government. As a result in 1906, the Qajar monarch gave Iran its first Constitution and parliament.