Sir Steven Runciman (1903- 2000) was a leading expert on the history of the Byzantine Empire and the Crusades. His three-volume work, A History of the Crusades, was published in 1951–54 to wide acclaim and was followed by The Fall of Constantinople, 1453 (1965), another highly praised work. Runciman served as a lecturer at the University of Cambridge from 1932 to 1938 and as a professor of Byzantine art and history at the University of Istanbul from 1942 to 1945, but for most of his life he was an independent scholar.