 It was part of one of the oldest hospitals in London, St Thomas' Hospital established in 1173 but whose roots can be traced to the establishment of St Mary Overie Priory in 1106.According to historical records "St Thomas's Hospital Medical School" was founded in about 1550.It was admitted as a school of the University of London in 1900 but remained a constituent part of "St Thomas' Hospital" until 1948 when it formally became part of the university.