The Hornsey Parish boundary ran from Stoke Newington, in the south, through Stroud Green to Highgate in the west, and from near Colney Hatch in the north, past Muswell Hill, and a detached portion of Clerkenwell Parish, eastwards to the Tottenham Parish border and then along Green Lanes back to Stoke Newington.
The Hornsey vestry established a Public Health and Drainage committee in 1851; this committee only had a short life as it was replaced, in 1854, with a Highways Board, and a full Local Board was established in 1867.
The Local Board gave way to the Urban District Council in 1894/5 which governed the Parish until 1903, when it became obtained Borough status.
In 1865, the southern part of the parish, consisting of the Brownswood Park area and the detached pieces surrounded by the parishes of Hackney and Stoke Newington adopted the Local Government Act 1858, and formed the South Hornsey Local Board.
In 1899 the South Hornsey urban district and civil parish were absorbed by the Metropolitan Boroughs of Stoke Newington and Islington in the County of London.