During the 1930s, Turkey-Iraq relations were at their most cordial, with both the Hashemite King Ghazi (1912–1939) of Iraq and Kemal Ataturk (1881–1938), the founder of the modern Turkish state and its leader since 1923, continuing to maintain close relations with the British. Although there was some conflict over border issues and resource questions, the relations of both states remained relatively stable, limited, and oriented toward the West.
From the late 1930s, after the deaths of both Ataturk and Ghazi, to the 1970s, Turkey and Iraq each suffered a series of military coups alternating with democratically elected governments with strong military elements. Relations between the two states focused on issues that remained significant for the rest of the twentieth century, transcending whatever regime happened to be in power, and institutionalizing the pragmatism of their ties.
The 1940s saw differences emerging in Turkey-Iraq foreign relations, with Iraq shifting support away from Europe. Iraq took part in the first Arab-Israeli war (1948) and, in the early 1950s, examined the possibility of a union between itself and Syria. Turkey opted to look in the other direction, supporting the Western states and, after its ascension to the North Atlantic Treaty Organization in 1952, placing itself firmly in the sphere of Western influence. Different foci in their extended foreign relations, however, did not preclude Iraq and Turkey from cooperating in common areas of interest. In 1955, both countries joined with Iran, Pakistan, and the United Kingdom to form the Baghdad Pact, a mutual-defense organization intended to contain the growth of Soviet influence in the region. This experiment ended when Iraq, after alienating many of its Arabic neighbors by joining the pact, found itself with a new military government and withdrew from the agreement.
The historically sensitive issue of water rights became a strong point of contention for the two countries beginning in the 1960s, when Turkey implemented a massive public-works project aimed at harvesting the water from the Tigris and Euphrates rivers through the construction of a series of dams, for irrigation and hydroelectric energy purposes. The intended level of control of common water resources by Turkey upon completion of the GAP project was unacceptable to Iraq, which remains dependent upon both rivers to supply a significant portion of its water needs.
First raised in the 1920s, the Kurdish question became a prominent concern of both Iraq and Turkey with the radicalization of a Kurdish independence movement and the formation of the Kurdistan Workers' Party (PKK) in the 1970s. Operating primarily out of Turkey, the PKK's revolutionary activity was aimed at the establishment of a Kurdish state in Turkey's southeast. For Iraq, the situation was less volatile, as divisions among the Kurds in northern Iraq prevented any real challenge to Baghdad's rule. However, as the Kurdish issue was a cross-border concern, it took center stage in Turkish-Iraqi relations during the 1970s and the 1980s.
The establishment of military-backed regimes in Turkey and Iraq by 1980 helped strengthen relations on several core issues, as both governments supported secularist and antiradical policies, stable borders, and closer ties with the West—needed by Iraq for its conflict with Iran and by Turkey in its desire to join the European Union. The Iraqi invasion of Kuwait in 1990, under the orders of former President Saddam Hussein, reversed this decades-long trend as Turkey again chose to support the West.
Iraq, often ignored Turkey's close ties with the United States, out of the desire to maintain relations with the country that, since the 1930s, had been one of Iraq's most significant trading partners and remained one of the few outlets for Iraqi goods. Iraq also generally ignored the periodic incursions into its territory by Turkish forces pursuing PKK groups, a continuing threat to Turkey, but mostly harmless to Iraq, as Kurdish factions remained disunited.
While foreign relations diverged after the Persian Gulf War, Turkey-Iraq relations have remained closely defined by parameters established decades earlier, dependent upon both local circumstances and foreign influence.