St Mary, Haggerston, was an Anglican parish church built to the designs of John Nash in 1827, in what is now the London Borough of Hackney. Built in the Gothic style of its time, it had an elaborate west front with a disproportionately tall tower. The rest of the church was, in comparison, rather plain. It was altered later in the 19th century by James Brooks as the first initiative of the Haggerston Church Scheme and destroyed by bombs during the Second World War. The site is now a children's playground west of Haggerston Park, between Thurtle Road and Queensbridge Road.
St Mary, Haggerston, was a "Commissioners' church", built under an Act of Parliament of 1818 which granted £1,000,000 for the building of new churches. The Church Building Commission, set up under the act to distribute the money and oversee construction, was advised on architectural questions by the Board of Trade, whose three architects, John Soane, John Nash and Robert Smirke were asked for sample plans and estimates as soon as the act was passed. Nash built only two churches for the commissioners: the Neoclassical All Souls, Langham Place, and the Gothic St Mary, Haggerston.
Once a hamlet in the parish of St. Leonard, Shoreditch, Haggerston had developed into an increasingly populated suburb of London by the time the church was built, and an increasingly industrialised one, with the opening of gasworks along the Regent's Canal from 1822, and the growth of various manufacturing industries.
The church was consecrated by the Bishop of London on 29 March 1827. The estimated cost of construction was £12,496 and it was designed to seat 1,700 worshippers.
The church had a substantial west front with side turrets, from the centre of which rose an unusually tall tower. Various apocryphal stories grew up to account for the great height of the attenuated tower. Its construction to such a height was made possible by the purchase by the contractor of a large amount of moderately priced Bath stone from the demolished Wanstead House.