William L. Langer
William Leonard Langer (March 16, 1896 – December 26, 1977) was the chairman of the history department at Harvard University. He was on leave during World War II as head of the Research and Analysis Branch of the Office of Strategic Services. He was a specialist on the diplomacy of the periods 1870-1900 and 1937-1941. He edited many books, including a series on European history, a large-scale reference book, and a university textbook.
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