With an initial size of and being largely rural in character, the shire ceded land to metropolitan Melbourne as suburban development encroached. On 6 January 1922 and 5 February 1941, the City of Footscray annexed two parcels of land totalling about 700 hectares. On 20 February 1957, the Altona Riding of the Shire of Werribee was severed and incorporated as the Shire of Altona, which became a City eleven years later. After this, the boundaries remained fairly stable, and on 20 March 1987 Werribee was proclaimed a City.