World War I casualties
The total number of military and civilian casualties in World War I were about 40 million: estimates range from 15 to 19 million deaths and about 23 million wounded military personnel, ranking it among the deadliest conflicts in human history.
Middle Eastern theatre of World War I
Allied military losses are placed between 1,000,000 and 1,500,000 including killed, wounded, captured or missing. This includes 303,000 British Empire and French casualties in Gallipoli, 601,000 British Empire casualties in Sinai-Palestine, at least 140,000 Russian casualties in the Caucasus, and 256,000 British Empire casualties in Mesopotamia, as well as additional Russo-British losses in Persia. Most of the British casualties were non-battle casualties; total British battle casualties inflicted by the Ottomans were estimated as 264,000 by Field Marshal Lord Carver. In addition to these were over 11,000 casualties sustained by Italians fighting Ottoman-backed Senussi tribesmen in the first half of 1915 alone, with unknown losses for the Senussi themselves.