Iran-Iraq conflict had deep roots in the history of the Middle East region. There were some historical and some immediate factors that gave rise to the war. The background of the conflict between the two countries shows that contemporary issues are inherited from the past. The history of competition and rivalry dates back to the Ottoman Turkish empire(1517-1918) and the Persian Empire under Safavids(1501-1722). Disputes between them revolved around geographical boundaries and interference in internal affairs, conducted by sectarian and ethnic minorities across the common border. Though the context of disputes changed the nature of conflict remained the same throughout. Until the early nineteenth century, migratory tribes in frontier areas militated against fixed borders and after that conflict continued under European Imperial powers. After the 1920s, Iran and Iraq were nominally independent and circumstances were different but animosities continued unaltered, at first under direct British influence and after 1985 as genuinely independent countries (Hiro 7).
Since the 1960s, serious confrontations between Iran and Iraq were going on. Initially, it involved support for subversive movements and territorial conflicts, later it revolved around the disposition of Shatt-al-Arab waterway. This waterway has been a bone of contention between the two countries since the Ottoman Empire due to the fact that it is a critical route for transportation. Under Shah’s regime, with United States diplomatic support and military aid, Iran rules the region and made unlawful encroachments in many other regimes of the Gulf (Levy and Froelich 128).
In 1969 Iran declared void a 1937 treaty giving Iraq virtually full control over the Shatt-al-Arab, and two years later seized from Arab emirs three small islands(Abu Musa and the Greater and Lesser Tunbs)near the Strait of Hormuz. At Algiers in 1975, Iraq agrees to redefine the Shatt boundary by the thalweg principle, ceding half of the waterway to Iran, in return for an end to the shah’s support of Iraqi Kurdish insurgents who had engaged Baghdad in a protracted and costly rebellion. (Levy and Froelich 128)