On November 2, 1917, Britain issued the Balfour Declaration:
According to the Peel Commission, appointed by the British Government to investigate the cause of the 1936 Arab riots, "the field in which the Jewish National Home was to be established was understood, at the time of the Balfour Declaration, to be the whole of historic Palestine, including Transjordan."
The Mandate for Palestine's purpose was to put into effect the Balfour Declaration. It specifically referred to "the historical connections of the Jewish people with Palestine" and to the moral validity of "reconstituting their National Home in that country." The term "reconstituting" shows recognition of the fact that Palestine had been the Jews' home. Furthermore, the British were instructed to "use their best endeavors to facilitate" Jewish immigration, to encourage settlement on the land and to "secure" the Jewish National Home. The word "Arab" does not appear in the Mandatory award.
The Mandate was formalized by the 52 governments at the League of Nations on July 24, 1922.