There are two large peoples in Iraq, Arabs and Kurds. 97% are Muslims, of which more than 50% are Shi'is, the rest are Sunnis

Arabs and arabized peoples constitute about 80% of the population. Kurds make up about 15% of the population. Other small groups are Iranian peoples living along the border to Iran.

The recent decades have seen many serious problems problems in the relationship between the Arab majority and the Kurds, who makes up the majority of the north. The Kurds have for a long time fought for their own independence, and they have an identity of their own, and speak Kurdish. However, tensions between Kurdish groups made it possible for Iraq to regain control over the region in 1996.

The second line of division run between Sunnis and Shi'is. The Shi'is constitute the clear majority in the south, and they did try to cut themselves off from Baghdad after the Gulf War of 1991.

There are other religious groups in Iraq, where Christians of various sects make up about 3%. Small, but important in the understanding of history of religions, are the Yazidis with about 100,000 members, and Mandeans with about 20,000 adherents. There are also about 2,500 Jews living in Baghdad.

Although members of the ruling Baath Party generally are ideologically committed to secularism, about 95 percent of Iraqis are Muslim and Islam is the officially recognized state religion. Islam came to the region with the victory of the Muslim armies under Caliph Umar over the Sassanians in A.D. 637 at the battle of Al Qadisiyah.

The majority of inhabitants soon became Muslim, including the Kurds, although small communities of Christians and Jews remained intact in the area of present-day Iraq. Iraq has been the scene of many important events in the early history of Islam, including the schism over the rightful successor to the Prophet Muhammad