The nascent Hashemite Kingdom over Greater Syria was forced to surrender to French troops on 24 July 1920 during the Battle of Maysalun; the French occupied only the northern part of the Syrian Kingdom, leaving Transjordan in a period of interregnum. Arab aspirations failed to gain international recognition, due mainly to the secret 1916 Sykes–Picot Agreement, which divided the region into French and British spheres of influence, and the 1917 Balfour Declaration, which promised Palestine to Jews. This was seen by the Hashemites and the Arabs as a betrayal of their previous agreements with the British, including the 1915 McMahon–Hussein Correspondence, in which the British stated their willingness to recognize the independence of a unified Arab state stretching from Aleppo to Aden under the rule of the Hashemites.
The British High Commissioner, Herbert Samuel, travelled to Transjordan on 21 August 1920 to meet with Al-Salt’s residents.
He there declared to a crowd of six hundred Transjordanian notables that the British government would aid the establishment of local governments in Transjordan, which is to be kept separate from that of Palestine. The second meeting took place in Umm Qais on 2 September, where the British government representative Major Fitzroy Somerset received a petition that demanded: an independent Arab government in Transjordan to be led by an Arab prince (emir); land sale in Transjordan to Jews be stopped as well as the prevention of Jewish immigration there; that Britiain establish and fund a national army; and that free trade be maintained between Transjordan and the rest of the region.
Abdullah, the second son of Sharif Hussein, arrived from Hejaz by train in Ma’an in southern Transjordan on 21 November 1920 to redeem the Greater Syrian Kingdom his brother had lost. Transjordan then was in disarray, widely considered to be ungovernable with its dysfunctional local governments. Abdullah gained the trust of Transjordan’s tribal leaders before scrambling to convince them of the benefits of an organized government. Abdullah’s successes drew the envy of the British, even when it was in their interest. The British reluctantly accepted Abdullah as ruler of Transjordan after having given him a six-month trial. In March 1921, the British decided to add Transjordan to their Mandate for Palestine, in which they would implement their “Sharifian Solution” policy without applying the provisions of the mandate dealing with Jewish settlement. On 11 April 1921, the Emirate of Transjordan was established with Abdullah as Emir.
In September 1922, the Council of the League of Nations recognized Transjordan as a state under the terms of the Transjordan memorandum. Transjordan remained a British mandate until 1946, but it had been granted a greater level of autonomy than the region west of the Jordan River. Multiple difficulties emerged upon the assumption of power in the region by the Hashemite leadership. In Transjordan, small local rebellions at Kura in 1921 and 1923 were suppressed by the Emir’s forces with the help of the British. Wahhabis from Najd regained strength and repeatedly raided the southern parts of his territory in (1922–1924), seriously threatening the Emir’s position. The Emir was unable to repel those raids without the aid of the local Bedouin tribes and the British, who maintained a military base with a small RAF detachment close to Amman.
The Treaty of London, signed by the British Government and the Emir of Transjordan on 22 March 1946, recognized the independence of Transjordan upon ratification by both countries’ parliaments. On 25 May 1946, the day that the treaty was ratified by the Transjordan parliament, Transjordan was raised to the status of a kingdom under the name of the Hashemite Kingdom of Transjordan, with Abdullah as its first king. The name was shortened to the Hashemite Kingdom of Jordan on 26 April 1949. 25 May is now celebrated as the nation’s Independence Day, a public holiday. Jordan became a member of the United Nations on 14 December 1955.