Mesopotamia the core of modern Iraq was at the heart of the Sumerian, Babylonian and Assyrian empires between the seventh century BC and AD 100. After brief spells under the rule of the Romans and the Sassanids (a minor regional power at the time), the Arabs conquered Iraq in AD 633. The Arab Caliphate had control of the territory during the late 12th and early 13th centuries before being dislodged by the Mongols. At the end of the 14th century Iraq, Azerbaijan to the north, Persia and parts of Turkey, Syria and Transcaucasia were conquered and subsumed into the empire ruled by Timur (also known as Tamerlane). The Turks were the next imperial invaders, ruling from the early 1500s until the collapse of the Ottoman Empire at the end of World War I.
In 1920, Iraq was placed under a League of Nations mandate administered by the UK, whose forces had occupied most of the country. The Hashemite Amir Faisal ibn Hussain, brother of the new ruler of neighbouring Jordan, Abdallah, was proclaimed King in 1921. The country achieved independence in 1932, but British forces intervened once again in 1941 to prevent a pro-Nazi coup. British troops were finally withdrawn in 1947. In 1958, the Hashemite Dynasty was overthrown by a group of radical army officers inspired by the example of Gamal Abdel Nasser in Egypt, and led by Brigadier Abdul al-Karim Kassem. The new regime failed to consolidate its position, however, and relied on a precarious coalition of forces, which quickly disintegrated.
After Kassem was killed in 1963 during a further coup, Colonel Abdul Salem Muhammed Aref set up a new Government. Iraq declared war on Israel at the outbreak of the Six-Day War in June 1967, although Iraqi forces were not engaged. In 1968, Iraq's final coup in recent history brought to power the Ba'ath Party. Ba'ath ideology espouses pan-Arabism, socialism and resistance to foreign interference, although many political scientists have noted its similarity to European fascism. Ba'athism was originally brought into Iraq from Syria during the 1950s and grew quickly. As it did so, however, the Syrian and Iraqi strains grew apart from one another and by the end of the 1960s were mutually hostile.
Since then, relations between Iraq and Syria have deteriorated still further: a decade later, Syria was a willing participant in the USA-led coalition which expelled Iraqi occupation forces from Kuwait. In July 1979, after a power struggle within the Ba'ath Party, Vice President Saddam Hussein took over as President and party leader. Saddam's main objectives were to establish his country as the undisputed leader of the Arab world and to overcome the Arabs' two principal enemies in the Middle East, Iran and Israel. Saddam reached the top at a time of escalating tension between Iran and Iraq. Iran appeared to be in chaos following the Islamic revolution which overthrew the Shah. The Iraqis perceived a good opportunity to resolve a long-running territorial dispute over the Shatt al-Arab waterway which feeds the Gulf and divides the two countries.
The Iraqis revoked a settlement of the dispute reached in 1975 and launched a full-scale invasion of Iran in September 1980. In the face of unexpectedly stiff Iranian resistance, the Iraqis failed to win the decisive military victory they had hoped for and the war degenerated into one of attrition, employing tactics similar to those of World War I. As in Europe 70 years earlier, use was made of poison gas initially against massed ranks of Iranian troops and then later against the civilian population. This was the first confirmation of Iraq's possession of weapons of mass destruction as well as a huge arsenal of conventional weaponry.
The fighting lasted until August 1988 when the two exhausted nations sued for peace with Iraq having made some minor territorial gains. The Iraqi economy was crippled and had incurred an enormous foreign debt, much of which was owed to neighbouring Kuwait: this became a serious source of friction between the two Governments over the next two years.
Insistent demands by the Kuwaitis for repayment, Iraq's historical claim over Kuwaiti territory (dating back to the 1920s), and a dispute over oil reserves provided the main pretext for the Iraqi invasion of Kuwait in August 1990. The American-led response to the invasion, which received firm backing from the UN in the form of mandatory sanctions and an authorisation to use military force, surprised the Iraqis. By the beginning of March 1991, the Iraqi armed forces had suffered a massive defeat and the Iraqi regime itself was under serious threat from armed opposition elements among the predominantly Shia population of southern Iraq and the Kurds in the north. However, the superior firepower of Iraqi troops some held in reserve, some reorganised from units fleeing the UN coalition was sufficient to defeat the rebels. The Western refusal to provide effective backing for the rebels was based on the lack of a UN mandate (which had only endorsed the expulsion of Iraqi forces from Kuwait) as well as the practical fear of a 'Balkanised' post-Saddam Iraq whereby the country splits into three mutually antagonistic entities (Shia, Sunni and Kurdish, respectively).
Thereafter, the USA, supported by Britain and others, used several means to constrain Iraq. 'No-fly' zones were established, covering the north and south of the country, in which all Iraqi air movement was forbidden (this allowed the Kurds to create an effectively autonomous region within the country). A UN Special Commission (UNSCOM) was formed to try to locate and destroy the remaining stocks and production facilities of Iraq's nuclear, chemical and biological warfare programmes. Iraq was also subject to a complete trade embargo excepting a strictly controlled regimen of oil sales, the proceeds of which the Iraqi Government could use to buy food and medicines.
By 1998, Iraq had developed sufficient means of circumventing sanctions and political confidence to throw out the UNSCOM inspectors. International support for the sanctions regime had waned to the point where only the US and Britain still backed its continued use. The two countries policed the 'no-fly' zones and launched occasional bomb attacks (about one a month) on Iraqi military and strategic installations.
In March 2003, the US-led coalition declared war on Iraq and, in April, successfully ousted the regime of Saddam Hussein. As a result, Iraq is undergoing a period of transition. Most of the country's political, social, physical and economic infrastructures have, by and large, been destroyed and are in the lengthy process of being rebuilt. The USA formed the Office of Reconstruction and Humanitarian Assistance (ORHA) to administer the country on an interim basis, provide humanitarian aid, rebuild infrastructure and help establish a representative Government. After much anticipation, the transferral of power was finally granted to a new Iraqi Government in mid-2004. This was supplemented by countrywide elections on January 30 2005 to appoint a 275-member National Assembly, of which the majority of seats have been democratically assigned to the Shia United Iraqi Alliance (although, contentiously, some people were unable to vote due to dangerous conditions and many Sunni Muslims did not participate in the electoral process for various reasons). This assembly elected a President, Jalal Talabani, and two deputies, Ghazi Yawer and Adel Abdul Mahdi, who, in turn, designated Ibrahim Jaafari as Prime Minister responsible for the day-to-day running of Iraq. Meanwhile, there have been no discovered weapons of mass destruction which provided the pretext for invasion. Iraq's future, despite the hope that the elections in early 2005 have given to some, remains highly uncertain. In November 2005, UN Security Council Resolution 1637 (2005) extended backing for the Multinational Force's role in Iraq for a further year.