Ethnic and Religious Groups of Iraq
In order to understand Iraq's current, complex political situation, it is necessary to understand the various ethnic and religious groups that share the country.
According to the CIA World Factbook, Iraq is the 40th largest country in the world in terms of population. (By comparison, its larger neighbor Iran has the world's 18th largest population.) Ethnically speaking, the majority of Iraqis are Arabs, though a sizeable Kurdish minority, estimated to be 15-20% of the country's total population, lives in the north. The region of Kurdistan is not an independent state, but comprises parts of eastern Turkey, northwestern Iran and northern Syria, in addition to northern Iraq. Kurds speak their own language, and in Iraq Kurdish is recognized as one of the national languages.
In religious terms, 97% of Iraqis are Muslims, with a tiny Christian minority and, historically, a Baghdadi Jewish minority, which mostly left the country when the state of Israel was founded. Of the Muslim population, approximately one-third are Sunni and two-thirds are Shia. The distinction between Sunni Muslims, who make up the majority of Muslims in the world, and Shia Muslims essentially comes down to who the Prophet Mohammad's rightful successor is deemed to be. Sunnis believe that the caliphs (heads of state) succeeded Mohammad, while the Shia believe that the imams (spiritual leaders) are the true heirs to Mohammad's teachings.
The legacy of Saddam Hussein is one of lingering resentment among all these groups. When Saddam was in power, his Baath Party granted social, political and economic privileges to the Sunni minority, while most Shia lived in poverty and political powerlessness. That is why a civil war, in which Shia enacted revenge upon Sunni, was such a feared outcome in Iraq after the invasion.
Likewise, Saddam exerted oppression, to a genocidal degree, over the Kurds. The Halabja poison gas attack near the end of the Iran-Iraq War, which killed thousands, is the largest chemical weapons attack against civilians in history. The attack was initiated in order to quell rebellion among the Kurds, some of whom were affiliated with the Iranian enemy, and came at the end of a three-year military campaign by Saddam against the Kurdish people. It is no surprise that the Kurds were quick to offer assistance to coalition forces during the invasion to overthrow Saddam.
Now that Saddam is no longer running the country, and U.S. troops are on their way out, it will be difficult, but not inconceivable, for these groups to overcome their past history and work together for a stable and democratic Iraq.