Lyon Sprague de Camp (November 27, 1907 – November 6, 2000) — known as L. Sprague de Camp — was an American writer of science fiction, fantasy, non-fiction and biography. In a career spanning 60 years, he wrote over 100 books, including novels and works of non-fiction, including biographies of other fantasy authors. He was a major figure in science fiction during the genre's heyday in the 1930s and '40s.