Iran-Iraq War

The Iran-Iraq War was fought from 1980 to 1988 after Iraq under Saddam Hussein invaded Iran in September 1980, seeking to exploit the instability following Iran's 1979 Islamic Revolution and to resolve long-standing border disputes over the Shatt al-Arab waterway. The war quickly settled into static, heavily fortified trench warfare reminiscent of the First World War, punctuated by human-wave infantry assaults, extensive Iraqi use of chemical weapons against Iranian troops and Iraqi Kurdish civilians, and periodic long-range missile exchanges between the two countries' cities known as the War of the Cities. Neither side achieved a decisive breakthrough despite years of grinding attrition along a largely static front, and the conflict finally ended with a United Nations-brokered ceasefire under Security Council Resolution 598 in August 1988, restoring approximately the prewar border. The war ranks among the costliest conflicts of the twentieth century in military casualties, with both belligerent states suffering losses in the hundreds of thousands without either achieving its original war aims.