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.
Ethnic groups in Syria
Most Syrians speak Arabic, most are Sunni Muslims, but there are no accurate numbers or percentages of the various "majority" and "minority" groups. Sunni Arab Syrians could be anywhere between 70% and 79% as non-Arabic-speaking groups (mostly Kurds) are usually estimated at about 4%, non-Sunni Muslim groups (mostly Alawis) at less than 10% and Arabic-speaking Christians are 10%, but these are only indicative percentages.