The parish of St George Hanover Square encompasses the wealthy neighbourhoods of Mayfair, Belgravia and Pimlico - of which large areas were owned by the Grosvenor Estate and developed by master builder Thomas Cubitt - as well as part of Hyde Park. This VCH Short relates the history of the parish, from its inception in 1725, to its abolition with the establishment of the London County Council in 1900. The area was transformed through rapid urbanisation from largely undeveloped fields on the western fringe of London to becoming one of the most affluents parts of the metropolis, with developments centred on a series of grand squares, including Hanover, Grosvenor and Belgrave Squares. In detailed thematic treatments, the book explores the local government of the vestry, as well as institutions such as the schools, charities and St George’s Hospital, now based in South London. The wider political culture and the economy of the parish are described, from the aristocrats and servants of Mayfair, to the industries on the bank of the Thames, including manufactories and a distillery. Finally, it covers the religious life of the parish, the erection of new churches and chapels, and its division into ecclesiastical parishes and subdistricts as population boomed in the 19th century.