The parliamentary borough was coterminous with the civil parish of Islington and each of the four divisions consisted of a number of parish wards used for the election of vestrymen to the incorporated vestry, the local authority for the area.
[1] Constituencies throughout Great Britain and Ireland were reorganised by the Representation of the People Act 1918.
At the next parliamentary redistribution, prior to the 1950 general election, the seat was unchanged.
By the time of the next election in 1974, new constituencies had been drawn based on the London boroughs created in 1965.
The political parties had been making preparations for an election to take place, and the following candidates had been selected by the Autumn of 1939: