Clive Staples Lewis, commonly known as C. S. Lewis (29 November 1898 - 22 November 1963), was a novelist, poet, academic, medievalist, literary critic, essayist, lay theologian, broadcaster, lecturer, and Christian apologist. Born in Belfast, Ireland, he held academic positions at both Oxford University (Magdalen College), 1925-54, and Cambridge University (Magdalene College), 1954-63. He is best known for his fictional work, especially The Screwtape Letters, The Chronicles of Narnia, and The Space Trilogy, and for his non-fiction Christian apologetics, such as Mere Christianity, Miracles, and The Problem of Pain.