According to 2005 census Iran’s population is estimated 68,018,000.
The population is not homogeneous, although it has a Persian core that includes over half of the people. Azerbaijanis constitute almost a quarter of the population.
The migrant ethnic groups of the mountains and highlands, including the Kurds, Lurs, Qashqai, and Bakhtiari, are of the least mixed descent of the original Iranians.
In the Northern provinces, Turkic and Tatar influences are evident; Arab strains predominate in the southeast.
Islam entered the country in the 7th century AD and is now the official religion; about 90% of Iranians are Muslims of the Shiite sect.
The remainder, mostly Kurds and Arabs, are Sunnis.
Colonies of Zoroastrians remain at Yazd, Kerman, and other large towns.
In addition to Armenian and Assyrian Christian sects, there are Jews, Protestants, and Roman Catholics.