Clive Staples Lewis (29 November 1898 – 22 November 1963) was a British writer, literary scholar, and Anglican lay theologian. He held academic positions in English literature at both Magdalen College, Oxford (1925–1954), and Magdalene College, Cambridge (1954–1963). Lewis is best known as the author of The Chronicles of Narnia, but he is also noted for his other works of fiction, such as The Screwtape Letters and The Space Trilogy, and for his non-fiction Christian apologetics, including Mere Christianity, Miracles, and The Problem of Pain.

Lewis was a close friend of J. R. R. Tolkien, author of The Lord of the Rings. Both men served on the English faculty at Oxford University and were active in the informal Oxford literary group known as the Inklings. According to Lewis's 1955 memoir Surprised by Joy, he was baptized in the Church of Ireland but fell away from his faith during adolescence. Lewis returned to Anglicanism at the age of 32, owing to the influence of Tolkien and other friends, and he became an "ordinary layman of the Church of England". Lewis's faith profoundly affected his work, and his wartime radio broadcasts on the subject of Christianity brought him wide acclaim.

Lewis wrote more than 30 books which have been translated into more than 30 languages and have sold millions of copies. The books that make up The Chronicles of Narnia have sold the most and have been popularized on stage, TV, radio, and cinema. His philosophical writings are widely cited by Christian scholars from many denominations.

In 1956, Lewis married American writer Joy Davidman; she died of cancer four years later at the age of 45. Lewis died on 22 November 1963 from kidney failure, at age 64. In 2013, on the 50th anniversary of his death, Lewis was honoured with a memorial in Poets' Corner in Westminster Abbey.