Cyril Lloyd Elgood M.D., F.R.C.P., honorary physician to the king of Persia (Shah) (1893–1970) commonly referred to as Cyril Elgood was a British physician (graduate of St. Bartholomew's Hospital) and historian of medicine in Persia/Iran, best remembered for his breakthrough studies on the history of medical and educational advances of Persia during the period of the 1500s to mid 18th century. He was also known for his work at Her Britannic Majesty's embassy in Tehran, his service in the British army in British India starting in 1914, and his active role in quarantine facilitation during infectious disease outbreaks in south-west Iran.