Ottoman Iraq

Ottoman Iraq (Ottoman Turkish: خطهٔ عراقیه, romanized: Hıṭṭa-i ʿIrāqiyye, lit. the Iraq region) was the Ottoman name for the region of Mesopotamian that was under their control. Historians often divide its history into five main periods. The first began with Sultan Süleyman I's conquest in 1534 and ended with the Safavid capture of Baghdad in 1623. The second lasted from the Ottoman reconquest in 1638 to the start of Mamluk self-rule in 1749. The third period, from 1749 to 1831, was marked by the Georgian Mamluk dynasty's semi-autonomous governance. The fourth stretched from the Ottoman removal of the Mamluks in 1831 to 1869, when reformist governor Midhat Pasha took office. The fifth and final phase ran from 1869 until 1917, when British forces occupied Baghdad during the First World War.

Administratively, during the first period in the 16th century, Baghdad Eyalet encompassed much of the territory of modern Iraq. In the 17th century, the Ottomans had reorganized Iraq into four eyalets (Baghdad, Basra, Mosul, and Shahrizor). However, from the late 17th century, a trend of administrative unification began, with Basra coming under Baghdad's control from around 1705 and Mosul and Shahrizor following after 1780 during the semi-autonomous Mamluk period. Following this unification, Mamluk rulers such as Sulayman the Great were described as governing "all of Iraq", and the Ottomans themselves began referring to the region unofficially as "the land of Iraq". By 1830, and possibly earlier, these were being collectively referred to in official Ottoman correspondence as the region of Iraq, as attested in a letter from Sultan Mahmud II. The four eyalets were later consolidated in the 19th century into the vilayets of Mosul, Baghdad, and Basra, which were treated as a single "Iraq Region" (Hıtta-i Irakiyye).

For much of the early modern period, Iraq was a contested frontier in the Ottoman–Persian wars, with control over Baghdad frequently shifting between the two empires. During World War I, Iraq became the focus of fighting between the British Empire and the Ottoman Empire in the Mesopotamian campaign, culminating in the British occupation of Baghdad in 1917 and the establishment of the British Mandate of Mesopotamia in 1920.