King's College London (informally King's or KCL; formerly styled King's College, London) is a public research university located in London, United Kingdom, and a founding college of the federal University of London. King's is arguably the third-oldest university in England, having been founded by King George IV and the Duke of Wellington in 1829 and received its royal charter in the same year. St Thomas' Hospital, which is now a teaching hospital of King's College London School of Medicine, has roots dating back to 1173. King's became one of the two founding colleges of the University of London in 1836. It has grown through mergers, including with Queen Elizabeth College and Chelsea College of Science and Technology (in 1985), the Institute of Psychiatry (in 1997), and the United Medical and Dental Schools of Guy's and St Thomas' Hospitals and Florence Nightingale School of Nursing and Midwifery (in 1998).