C.S. Lewis’s middle name was Staples, making his full name Clive Staples Lewis.
Lewis was born Clive Staples Lewis in Belfast in 1898. The initials “C.S.” became the form by which he was known publicly, while family and friends often called him Jack. The nickname came from his childhood and remained part of his personal identity throughout his life.
The name Staples was inherited from his maternal family. It is not a title, an abbreviation for a university, or a reference to a literary society. Because Lewis usually signed his books “C.S. Lewis,” readers who know only the initials may not immediately recognize his full middle name.
Lewis used several forms of authorship across his career. He published literary scholarship, Christian apologetics, devotional works, and fiction, generally under C.S. Lewis. His Narnia books and books such as The Screwtape Letters made that abbreviated name internationally famous.