Writing as: Ronald Chartham, Ronald Seth
Ronald Sydney Seth (5 June 1911 – 1 February 1985) [is] an English writer who used the surname Chartham for his activity as a sexologist and the surname Seth for books about travel and espionage.
As a child Seth was a chorister at Ely Cathedral and a King's Scholar at King's Ely. He was educated at Cambridge University. Appointed Professor of Literature at the University of Tallinn, Estonia, Seth returned to London at the start of World War II, joining the BBC and helping to start the Monitoring Intelligence Bureau. In 1941 he was commissioned into the Royal Air Force and in 1942 joined the Special Operations Executive. Parachuted into Estonia, he was captured by and later defected to the Germans. He was trained by the Sicherheitsdienst (the SS intelligence agency) as an agent for a mission to Britain. He spent most of the rest of the war as an informer in the Oflag 79 prisoner-of-war camp, but in April 1945 was entrusted with a message of peace by Heinrich Himmler (head of the SS), which he carried to London via Switzerland.
Seth's career included teaching and counselling in European universities, lecturing to British university students on "How to Enjoy Sex" and serving as a counsellor in his own London clinic. He was an editorial consultant to Forum: The International Journal of Human Relations. During the 1970s, he lived in Malta with his second wife, Barbara McAdam Seth.