The creation of the constituency was recommended by the Boundary Commission in a report issued in 1917, and formally created by the Representation of the People Act 1918. It came into existence at the 1918 general election. As the borough of West Ham had only 120,586 electors on 15 October 1946, the relevant date for the subsequent Boundary Commission review, the borough was only entitled to two Members of Parliament; North and South divisions were recommended. As a consequence Silvertown was abolished as a separate constituency by the Representation of the People Act 1948 and went out of existence at the 1950 general election.
Silvertown was based on the two wards of Custom House and Silvertown (based either side of the Royal Victoria Dock), and Tidal Basin, which was to its north-west. The large wards in the southern County Borough of West Ham at the time of the 1917 Boundary Commission review made it necessary to split one ward across two constituencies, or else the divisions of West Ham would have had significantly different sizes. The ward which was split was the Canning Town ward, the southern part of which was included in Silvertown: the commissioners drew a line along the centre of the Woolwich branch of the Great Eastern Railway (now the North London Line) from Canning Town station north to join up with Star Lane (near the future Star Lane DLR station), then east along Star Lane, to join up with the ward boundary at Hermit Lane and Beckton Road.[1]