Corporation of London

St Thomas's Hospital originated in a small infirmary attached to the Augustinian Priory of St Mary the Virgin (St Mary Overie). The infirmary assumed the name of St Thomas the Martyr shortly after his canonization in 1173. The hospital was destroyed by fire in 1212 and was re-built at the south end of London Bridge. During the Reformation in 1540 the hospital, along with many other religious foundations, was dispossessed of its revenues and closed. Edward VI restored St Thomas's estates and revenues after the citizens of London petitioned for the hospital to be reinstated. The hospital re-opened with 120 beds and three Barber Surgeons, assisted by apprentices, were appointed. A royal charter of 1553 made the Mayor and Commonalty and Citizens of London perpetual Governors of the Hospital. The hospital underwent an extensive building programme between 1693 and 1709, and about 300 beds were provided.

In 1866 the extension of the railway from London Bridge to Charing Cross forced the Hospital to move to a temporary site at Newington until a permanent home was purchased in Lambeth, at the foot of Westminster Bridge. The land was bought from the Metropolitan Board of Works for £95,000. Queen Victoria opened the new building in 1871. Florence Nightingale, chose St Thomas's as the hospital in which to found her training school for nurses. During World War One the hospital has a military ward of 200 beds known as the 5th London (City of London) General Hospital.

St Thomas's Hospital was seriously disrupted by World War Two, when it was changed into a casualty clearance station, with sixteen wards closed and a limited out-patients' service. By March 1940 the anticipated aerial bombing had not taken place, and the out-patients' service resumed, 250 civilian beds reopened at Lambeth and the students of the medical school were recalled. However bombing raids in the Autumn severely damaged the hospital. Arrangements were made to move staff and patients to a hutted hospital at Hydestile, near Godalming. By 1943 St Thomas's Hospital comprised 184 beds at the London site, 334 in Hydesville and 50 maternity beds in Woking. By the end of the war four ward buildings, three operating theatres, most of the nurses' accommodation and a large section of the out-patients department had been destroyed by bombing.

In 1948 the hospital became part of the NHS. On 1 April 1974 St Thomas' Hospital became part of the St Thomas' Health District (Teaching) of Lambeth, Southwark and Lewisham Area Health Authority. On further reorganisation in 1982 this became West Lambeth Health Authority.