Unlike some other Muslim groups, Iraqis had little exposure to Western culture before immigrating to North America in the wake of the first Persian Gulf War (1991) and therefore had more difficulty assimilating. According to the U.S. census of 2000 and the Canadian census of 2001, 37,714 Americans and 26,655 Canadians claimed Iraqi ancestry. U.S. centers of settlement include the greater Detroit area, Chicago, and Los Angeles. About half of Iraqis in Canada live in Toronto. Iraq is the easternmost Arab nation, occupying 167,400 square miles. It is bordered by Jordan and Syria on the west, Turkey on the north, Iran on the east, and Kuwait and Saudi Arabia on the south. In 2002, the population was estimated at 23,331,985. The people are ethnically Arabs (65 percent), Kurds (23 percent), Azerbaijani (5.6 percent), and Turkmen (1.2 percent). More than 96 percent of Iraqis are Muslims, though there are clear divisions between the 62 percent Shia and 34 percent Sunni. The region known to the Greeks as Mesopotamia, the land between the Tigris and Euphrates Rivers, is the heart of Iraq. The well-watered river banks provided abundant crops and led to the development of the world’s first civilization around 3500 B.C. A succession of empires ruled by Arabs, Persians, Indo-Europeans, and Greeks controlled the region prior to its conquest by Muslim armies in the 630s. Baghdad was one of the most advanced and sophisticated cities in the world under the Abbasid caliphate in the ninth century but gradually declined in the face of Islamic divisions and eventual Mongol conquest in 1258. The Ottoman Turks ruled Iraq from the 16th century to 1917. After World War I (1914–18), Iraq was a territory mandated to British oversight and eventually gained full independence in 1932. After considerable political turmoil, including attempted Kurdish revolts (1945, 1974) and Communist control of the central government (1973), the Baathist Saddam Hussein gained office in 1979. Iraqis benefitted in the 1970s and 1980s from considerable oil revenues and resulting social improvement, but Hussein also took the country to war and brutally repressed all political opponents. In 1980, he launched an invasion of Iran, which led to a devastating eight-year war and the death of some 1 million Iraqis. In August 1990, Iraq invaded Kuwait, leading to U.S. involvement and the first Persian Gulf War (1991) in which the Iraqi army was largely destroyed. The terrorist attacks of September 11, 2001, heightened U.S. suspicions regarding Iraqi support for al- Qaeda and other terrorist organizations. This combined with Iraqi evasion of required United Nations inspections regarding the development of weapons of mass destruction, resulted in a U.S.-led invasion of Iraq in 2003. Saddam Hussein was captured by American forces on December 13, 2003. In April 2004 Iraqi leaders determined to put Hussein on trial for crimes committed during his rule, though public proceedings had not begun before the end of the year. On June 28, 2004, the U.S.-led coalition returned sovereignty to an Iraqi interim government, with nationwide elections scheduled for January 2005. About 140,000 U.S. troops remained in Iraq at the end of 2004. Prior to World War II (1939–45), only a few hundred Iraqis immigrated to North America, most from the privileged class and for economic opportunities. Many of these were minority Chaldean Christians, who began to settle in and around Detroit as early as 1910. By the end of World War II, the Chaldean population in Detroit numbered about 1,000. Although a few students came for study after the war, immigration remained small until the 1970s, when political events drove many dissidents from the country under the flag of pan-Arab unity, Hussein crushed a Kurdish revolt in 1975, and in 1979 began a systematic suppression of communists, Kurds, Shia Muslims, and Baathists who had fallen out of favor. About 300,000 Shias were driven to Iran, and many of those eventually made their way to the United States. The first extensive immigration, however, came only after the 1991 Persian Gulf War, when about 10,000 Iraqi refugees were admitted to the United States, mostly Kurds and Shiites who had assisted or sympathized with the U.S.-led war. Between 1992 and 2002, about 50,000 Iraqis immigrated to the United States, many as refugees. Between 1996 and 2001 alone, 14,000 Iraqi refugees were admitted. On April 9, 2003, hundreds of Iraqis celebrated in the streets of Dearborn, Michigan (suburban Detroit), celebrating the coalition capture of Baghdad and the overthrow of Hussein. In 2004, many recent Iraqi immigrants waited to see if conditions in the country would stabilize following the restoration of sovereignty to a new Iraqi government in June 2004, with an eye to returning to their home country. Iraqi immigration to Canada was largely the result of the disruptions of the Iran-Iraq War of the 1980s and the two Persian Gulf wars of 1991 and 2003. Between 1945 and 1975, there were no more than 200 Iraqi immigrants. With the rise of Hussein and the intensification of political persecution after 1979, a small but steady stream of dissidents left the country, with almost 6,500 coming to Canada by 1992. Of 25,825 Iraqis immigrants in Canada in 2001, only 2,230 (8.6 percent) came before 1981. With constant war and the brutal suppression of Kurds and Shiites by the Iraqi government, immigration increased in the 1990s. Between 1991 and 2001, almost 20,000 Iraqis immigrated to Canada. See also Arab immigration; Iranian immigration.