Who was C.S. Lewis’s older brother and longtime biographer?

C.S. Lewis’s older brother and longtime biographer was Warren Lewis.

Warren Hamilton Lewis, usually called Warnie, was born in 1895, three years before his younger brother. The brothers shared a close relationship, a love of imaginative stories, and a home life that included extensive reading. Warren later served in the British Army during the First World War and became a historian.

After retiring from military service, Warren lived near C.S. Lewis in Oxford and helped preserve records of his brother’s life. He wrote a biography of C.S. Lewis and edited parts of Lewis’s correspondence and diaries. Warren is sometimes confused with Albert James Lewis, their father, or with Lewis’s literary friends such as J.R.R. Tolkien, but Warren was the family member who documented his brother’s life most extensively.