David Marshall Lang (6 May 1924 – 20 March 1991), was a Professor of Caucasian Studies, School of Oriental and African Studies, University of London. He was one of the most productive British scholars who specialized in Georgian, Armenian and ancient Bulgarian history.
David M. Lang was educated at Monkton Combe and St John’s College, Cambridge where he was a Major Scholar and later held a Fellowship. In his military career he was an officer in Iran during the Second World War. He was appointed in 1944 as acting Vice-Consul in Tabriz, Iran, where he acquainted himself with the city's Armenian population. In 1949 he was the member of staff for the School of Oriental and African Studies at University of London. He began as Lecturer in Georgian language, then as Reader and in 1964 he became Professor of Caucasian Studies. In 1953 he held a Senior Fellowship at the Russian Institute of Columbia University and in 1965 he was a visiting Professor in Caucasian Studies at the University of California, Los Angeles. Between 1962 and 1964 he was Honorary Secretary of the Royal Asiatic Society of London. He visited the Soviet republic of Armenia three times during the 1960s and 1970s. It was on one of these visits to the Soviet Union, in December 1963, that he was recruited by the KGB, according to KGB files copied in Moscow by archivist Vasili Mitrokhin.