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. Its first member was Labour's Will Thorne who won with an impressive 94.9% of the popular vote, a record for an English parliamentary seat held to this day. 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 Plaistow was abolished as a separate constituency by the Representation of the People Act 1948 and went out of existence at the 1950 general election.