Religion in Iraq
Islam is the official state religion in the Republic of Iraq, but the constitution guarantees freedom of religion. Iraq is a multi ethnic and multi religious country with Islam, Christianity, Yazdanism, Zoroastrianism, Shabakism, Judaism, Mandaeism, Bahā'i, Ahl-e Haqq-Yarsanis, Ishikism and numerous other religions all having a presence in the country. Shia Islam is the main religion in Iraq followed by 60–65% of the population, while Sunni Islam is followed by 32–37% of the people. Many cities throughout Iraq have been areas of historical prominence for both Shia and Sunni Muslims, including Najaf, Karbala, Baghdad and Samarra.
Islam in Iran
Iran's population is about 82,000,000 people, and Islam is the religion of 99.4% of Iranians. Nearly 90% of Iranians are Shi'a and about 10% are Sunni. Most Sunnis in Iran are Kurds, Larestani people (from Larestan), Turkomen, and Baluchs, living in the northwest, northeast, south, and southeast. Almost all of Iranian Shi'as are Twelvers.