Britain extended its military control over the Palestinian territories in late 1918, marking the beginning of the British Mandate over Palestine. The administrative divisions in Palestine comprised two phases:
First Phase: The administrative and geographical division in 1922 included the Southern District, consisting of four districts; the Jerusalem-Jaffa District, comprising six districts; the Nablus District, encompassing four districts; and the Northern District, including five districts.
Second Phase: In 1939, Britain restructured the administrative divisions in the Palestinian territories, establishing six districts: the Galilee District, encompassing five districts; the Haifa District, comprising two districts; the Nablus District, including three districts; the Jerusalem District, consisting of three districts; the Jaffa District, including two districts; and the Gaza District, comprising two districts.