War and regime change in Iraq have increased worldwide awareness of the long-standing animosities between the country's Sunni and Shia Muslim populations, as well as deep divisions between the Arab majority and Kurd populations in the northern highlands.

This brief guide is intended as a starting point toward understanding why religious and ethnic complexities pose such a significant challenge to rebuilding, and provides links to more information in Encarta Encyclopedia.

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Historical background
The modern state of Iraq was created by the victorious Allies after the conclusion of World War I (1914-1918). During the war, the British had led Arab forces in rebellion against the Ottoman Empire, promising the Arabs independence if the Ottomans were defeated. With the defeat of the Central Powers (Germany, the Ottoman Empire, and Austria-Hungary), the British drew up a new map for the ancient land of Mesopotamia, creating Iraq, a country whose population included many tribal groups and pronounced religious and ethnic divisions.

After a brief period as a British mandate, Iraq was established as a monarchy in 1921. The new king, Faisal I*, faced a fractious society, which divisions among tribes, classes, and religious and ethnic groups threatened to tear asunder. Every Iraqi government since, including the dictatorship of Saddam Hussein, has confronted the difficulties of holding together a nation whose population is so riven by differences.

Religious divisions
Muslims make up 96 percent of Iraq's population, but sharp divisions exist between adherents to the Sunni and Shia branches of Islam.

The divisions stem from the 7th century, when Muslims split over the issue of who should rightly lead the Islamic community. Those who accepted the rule of the Umayyad family became known as Sunnis. Those who opposed the Umayyads in favor of the descendants of Ali, Muhammad's cousin and son-in-law, were known as Shias. The two sides eventually became different Islamic sects.

The majority of Iraqis--about 60 to 65 percent of the nation's Muslims--adhere to the Shia* branch of Islam. Shia Muslims live mostly in central and southern Iraq. The area encompasses the country's most productive agricultural region, and also includes strategically important southern cities such as Al Başrah* (Basra), an important oil-refining center, and Umm Qaşr, Iraq's main port city.

Iraq's Baath Party*, the ruling party under Saddam Hussein, was dominated by Sunni Muslims. Despite the Baathist movement's original intention to unite Arabs of all religious denominations against foreign domination, in practice Iraq's Baath Party suppressed Shia Muslims. As a result, poverty is particularly widespread among the Shias, including those who live in Baghdād. Few Shias are found in the middle and upper ranks of society.

Troubled relations between Sunni and Shia Muslims were intensified by the 1979 revolution in Iran, which overthrew the country's secular government and established a Shia-controlled government there. Iraq's rulers feared that the success of Iran's Shia revolution would incite Iraqi Shias against the Baathist government. Sunni-Shia religious animosities exacerbated the subsequent Iran-Iraq War (1980-1988), which resulted in over 1 million casualties.

In 1994 Iraq conducted a military campaign against Shia rebels in the southern marshlands. The Shias were quickly crushed.

Ethnic divisions
Ethnically, about 75 percent of the population of Iraq is Arab*. The Arabs include the Shia population and most of the Sunni Muslims of central Iraq. Kurds*, most of whom practice Sunni Islam, are considered distinct in ethnicity and language, and they form the largest ethnic minority, constituting 15 to 20 percent of the Iraqi population. Most Iraqi Kurds dwell in the highlands of northern Iraq. Smaller groups include Turkmens, Jews, Armenians, and Assyrians.

Iraq's provisional constitution defines the Iraqi people as comprising two principal nationalities, Arab and Kurdish. A 1974 amendment provides for autonomy for the Kurds in areas where they constitute a majority, but it stipulates that Iraq must remain united and undivided.

The Kurds have for centuries inhabited a mountainous region encompassing portions of southeastern Turkey, northern Iran, and northwestern Iraq. Demands for Kurdish autonomy or independence have been resisted, especially by Turkey and Iraq, which have both suppressed separatist movements and uprisings in recent decades.

Within Iraq, much of the Kurdish population is concentrated in and around the northern cities of Mosul* and Kirkūk*, an area encompassing Iraq's richest oil fields. Mosul lost more than half of its population between 1977 and the late 1980s, due in part to conflict between resident Kurds and the Iraqi government.

The outlook
With the United States-led invasion of Iraq, the divisions within Iraqi society took on strategic importance. The U.S. government justified the war, in part, as an effort to free the Iraqi people from a brutal dictatorship, and by all indications counted upon the support of the Shias of southern Iraq and the Kurds of northern Iraq.

In several cities in the Shia-dominated south, allied forces faced more resistance and distrust of American intentions than military planners seem to have anticipated. While many in southern Iraq held deep grievances against the Sunni-dominated government of Saddam Hussein, they also have the memory of being asked to revolt against his government following the first Persian Gulf War, and then being left without military support to face Saddam's troops.

In the north, Kurds cooperated more willingly with the U.S.-led forces. When organized Iraqi opposition collapsed, however, U.S. troops faced the new challenge of protecting Arab Iraqis in the north from Kurdish retaliation.

Many analysts wonder if postwar Iraq can hold together as a country. Will the Kurds push for greater autonomy, or even complete independence? Will the Shias demand a greater share of the nation's power and wealth, or will they, too, look to form an autonomous government? Complicating the postwar outlook is the anxiety that Turkey, which fears rebellion among its own Kurdish population, might feel compelled to intervene should the Iraqi Kurds move to establish an independent homeland. Meanwhile, the Iranian government might wish to support the Iraqi Shias in any attempts at self-rule.

The United States has indicated that a postwar Iraq will remain a unified nation, with fair and equitable treatment for all its ethnic and religious groups. But this goal eluded the British and the Iraqi monarchy, and achieving it now may prove a far longer and more difficult process than defeating the regime of Saddam Hussein.

Also on MSN Encarta
Encarta's overview of the war in Iraq
Interactive map of Iraq

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