Demographics of Iraq
97% of Iraqis follow Islam: 61% Shia and 34% Sunni. 1% of these describe themselves as "Just a Muslim". According to the CIA Factbook, Shias make up 60% of population, while Sunnis 35%. Christianity accounts for 5%, and the rest practice Mandaeism, Yazidism and other religions.
Culture of Yemen
Religion in Yemen primarily consists of two principal religious groups of Islam; Sunni and Shi'a. About 65% of the Muslim population is Sunni, and 30% is Shi'a. Sunnis are primarily Shafi'i, but also include significant groups of Malikis and Hanbalis. Shi'as are primarily Zaidis, though they also have significant minorities of Twelver Shi'as and Musta'ali Western Isma'ili Shi'as (see: Shi'a Islam in Yemen).
The Sunnis are predominantly in the south and southeast. The Zaidis are predominantly in the north and northwest, while the Jafaris and Isma'ilis are mostly located in the main centers of Sana'a and Ma'rib. There are mixed communities in the larger cities.