Clive Staples Lewis (29 November 1898 – 22 November 1963) was a British writer and lay theologian. He held academic positions in English literature at both Oxford University (Magdalen College, 1925–1954) and Cambridge University (Magdalene College, 1954–1963). He is best known for his works of fiction, especially The Screwtape Letters, The Chronicles of Narnia, and The Space Trilogy.