Thomas Baillie, was an officer of the Royal Navy. He saw service in the Seven Years' War, rising to the rank of captain. He was later appointed to the office of Lieutenant-Governor of Greenwich Hospital, but became involved in the celebrated libel case R v Baillie after he made accusations of mismanagement in the running of the hospital. He was later appointed to the post of Clerk of the Deliveries of the Ordnance, which he held until his death in 1802.

Greenwich Hospital was a permanent home for retired sailors of the Royal Navy, which operated from 1692 to 1869. Its buildings, in Greenwich, London, were later used by the Royal Naval College, Greenwich and the University of Greenwich, and are now known as the Old Royal Naval College. The word "hospital" was used in its original sense of a place providing hospitality for those in need of it, and did not refer to medical care, although the buildings included an infirmary which, after Greenwich Hospital closed, operated as Dreadnought Seaman's Hospital until 1986.