Britain's interest in Mesopotamia ran much deeper than just opening another front to harrass the Central Powers. They already had a significant economic toe-hold in Basra and Baghdad to the point that in 1911 the Viceroy of India recommended outright annexation by the India Office. Russia had always been perceived as a threat in the region (hence the Crimean war), but then unified Germany became a threat as well, especially with their planned Berlin-Baghdad railroad. The British managed to get two subjects appointed to the railroad board, and they were deeply involved in developing Basra port. The Ottoman sultan actually recognised British police authority in the Shatt al-Arab and Persian Gulf.

     Despite horrific initial setbacks, British imperial forces prevailed in the Mesopotamian theatre. Although the war-time Sykes-Picot agreement had awarded the Mosul villayet to the French, they were not there and at war's end the British rushed in to gain as much advantage as possible before the impending armistice. Because they already had such a major economic investment, British policy in Iraq was very different from western Arabia where they had overtly encouraged and aided the Arab Revolt. To do so in Iraq would have destabilised the India Office as well as further fragmented the mosaic of races in Iraq that neither the Ottomans nor the British had been able to bring together. Arab nationalism was to be controlled, not encouraged, although the "Sharifian" faction in London (e.g. T.E. Lawrence and Gertrude Bell "the uncrowned queen of Iraq") was trying to follow through on rewarding all Arabs for their war effort with full independence.

     In January 1919, the British set up a military administration under Sir Arnold Wilson, and in April 1920 the League of Nations confirmed the British Mandate over the region. Wilson's arrogant rule, however, helped set the stage for Great Arab Revolt in 1920.

• Turkish attempts to recapture Basra: 11-14 April 1915, by Chris Baker (The British Army in the Great War)

• The capture of Amara: 31 May - 4 June 1915, by Chris Baker (The British Army in the Great War)

• The capture of Nasiriyeh: 27 June - 24 July 1915, by Chris Baker (The British Army in the Great War)

• The (first) Advance on Baghdad: 12 September - 7 October 1915 : including the capture of Kut-al-Amara, by Chris Baker (The British Army in the Great War)

• The Battle of Ctesiphon: 22 - 24 November 1915, by Chris Baker (The British Army in the Great War)

• The retreat from Ctesiphon, and the siege of Kut: 25 November 1915 - 29 April 1916, by Chris Baker (The British Army in the Great War)

• The Battle of Sheikh Sa'ad: 7 January 1916, by Chris Baker (The British Army in the Great War)

• The Battle of the Wadi: 13 January 1916, by Chris Baker (The British Army in the Great War)

• The Battle of the Hanna: 21 January 1916, by Chris Baker (The British Army in the Great War)

• Attack on the Dujaila Redoubt: 7-9 March 1916, by Chris Baker (The British Army in the Great War)

• The Battles of the Hanna and Fallahiyeh: 5 - 8 April 1916, by Chris Baker (The British Army in the Great War)

• Commonwealth War Graves Commission

• World War One Cemeteries, by Brent Whittam, Ann Whittam and Terry Heard

• General History
  • Mesopotamia, by Chris Baker (The British Army in the Great War)
  • The Road To Basra - 1914, by Christopher Trevelyan
  • Iraq in World War I and the British Mandate, by US Library of Congress Country Study