From the Wikipedia page 
Southwark St George the Martyr was a civil parish in the metropolitan area of London and part of the ancient Borough of Southwark. In 1855 the parish vestry became a local authority within the area of responsibility of the Metropolitan Board of Works. It comprised 284 acres (1.15 km2) and had a population in 1881 of 59,712.
The bulk of the parish was centred around St George's Circus, with Newington Causeway and Borough High Street forming the eastern boundary. In the north east it included the church of St George the Martyr Southwark and then formed a long, narrow panhandle along the Old Kent Road, terminating at what is now Burgess Park and surrounding the triangular parish of Newington on two sides.
It became part of the Metropolitan Borough of Southwark in 1900 and was abolished as a civil parish in 1930.
Information about the church can be found here .