Electoral Calculus categorises the seat as being part of the “Strong Left” demographic, those who have very economically left wing and socially liberal views, and have an internationalist outlook including strong opposition to Brexit: only 21.6% of Islington North voted for Brexit in 2016, indicating that it is a heavily pro-Remain area.

The constituency was defined in the legislation as consisting of the single ward of Upper Holloway of the parish of Islington.

[6][7] Under the next redistribution of seats by the Representation of the People Act 1918 constituencies in the County of London were defined in terms of wards of the metropolitan boroughs created in 1900.

[7][8] At the next redistribution of seats by the Representation of the People Act 1948 the constituency was again defined as Tollington, Tufnell and Upper Holloway wards of the Metropolitan Borough of Islington, with boundaries as they existed at the end of 1947.

Islington North was defined as comprising seven wards: Highview, Hillmarton, Hillrise, Junction, Parkway, St. George's and Station.

These were Gillespie, Highbury, Highview, Hillrise, Junction, Mildmay, Quadrant, St. George's, Sussex and Tollington wards.

This reflects the depopulation of central London on a lowering of adult occupancy of households and the local authority has replaced tower blocks.

The criteria of successive reviews emphasise equal electorates as well as restricting seats to one or, if unavoidable, two local authority areas.

In the ten elections since Corbyn began representing the constituency, the Conservatives have finished in second place five times while the Liberal Democrats have also been runners up on five occasions.

[45] Michael O'Halloran, elected Labour MP for Islington North in 1969, was the subject of an investigation in the early-1970s by The Sunday Times newspaper.

O'Halloran sought selection as the SDP candidate for the revised Islington North constituency but the local SDP association selected John Grant, then-SDP (elected as Labour) MP for Islington Central, as their official candidate.