In late June 1914, Archduke Franz Ferdinand of Austria was assassinated by a Serbian nationalist in Sarajevo, Bosnia. An escalation of threats and mobilization orders followed the incident, leading by mid-August to the outbreak of World War I, which pitted Germany, Austria-Hungary and the Ottoman Empire (the so-called Central Powers) against Great Britain, France, Russia, Italy and Japan (the Allied Powers). The Allies were joined after 1917 by the United States.
War I ended in the defeat of the Central Powers in November 1918, more than 9 million soldiers had been killed and 21 million more wounded.
Source: World War I History - World War I - HISTORY.com

During WWI the combatants were on the one hand, the Ottoman Empire (including Kurds, Persians and some Arab tribes), with some assistance from the other Central Powers, and on the other hand, the British (with the help of Jews, Greeks, Assyrians and the majority of the Arabs), the Russians (with the help of Armenians) and the French from the Allies of World War I.
Source: Middle Eastern theatre of World War I - Wikipedia

The Ottomans ran a multilingual, multireligious empire, ruled by a sultan who also bore the title of caliph--commander of all the world's Muslims. Having joined the losing side in the Great War, however, the Ottomans saw their empire summarily dismantled by European statesmen who knew little about the region's people, geography and customs.
  The secret Sykes Picot agreement of 1916 divvied up the Middle East between Britain and France.
  The resulting Middle Eastern states were often artificial creations.
See Remapping the Middle East


The Armenian Genocide occurred in this period (1915-1918). Ottoman government's systematic extermination of its minority Armenian subjects inside their historic homeland, which lies within the territory constituting the present-day Republic of Turkey. The total number of people killed as a result has been estimated at between 800,000 and 1.5 million.
The Arab revolt (1916-1918) had the aim of securing independence from the ruling Ottoman Turks and creating a single unified Arab state spanning from Aleppo in Syria to Aden in Yemen. Arab Muslims were called to sacred rebellion against the ostensibly "impious" Ottoman government. Contrarily, Turks accuse rebelling tribes for betraying the Muslim Caliphate during his campaign against imperialist powers which were trying to divide and govern the Muslim lands.
Lawrence of Arabia (Thomas Edward (T.E.) Lawrence) -
There were 8 or more campaigns in the Middle East during the WWI, but the Arab campaign, a minor one, is well known because of Lawrence and the subsequent movie which won seven in total including Best Director, Best Sound Editing, Best Film Editing, and Best Picture.
In 1916 the British Army sent Lawrence to meet the Amir Feisal whose tribesmen had been attempting to besiege Medina. Feisal and Lawrence developed an immediate rapport. Feisal's men were keen fighters but hopelessly ill-disciplined. Lawrence and his Arab followers captured Aqaba from the rear after defeating a whole Turkish battalion. As the revolt became more successful, more and more Arab tribesmen joined it. Lawrence led an attack on the Turks at Tafila as part of the Damascus campaign, in which a whole battalion was destroyed. On October 31st, 1918, an armistice was concluded with the Turks.
Lawrence accompanied the Arab delegation to the Versailles Peace Conference where they fully expected their reward for helping the Allies in the war - full independence. Britain and France carved up the Middle East into their own zones of influence and the French even ejected Feisal from Damascus.
On November 2, 1917, Britain issued the Balfour Declaration:
His Majesty's Government views with favor the establishment in Palestine of a national home for the Jewish people, and will use their best endeavors to facilitate the achievement of this object, it being clearly understood that nothing shall be done which may prejudice the civil and religious rights of existing non-Jewish communities in Palestine or the rights and political status enjoyed by Jews in any other country.

Links:
Middle East Empires

last updated 8 Nov 2014