What was C.S. Lewis's full first name?

C.S. Lewis's full first name was Clive Staples. He was born Clive Staples Lewis in Belfast, Ireland, on 29 November 1898.

The initials “C.S.” became the form by which Lewis was publicly known, but they did not stand for a conventional pair of given names. “Staples” was his mother’s surname, and “Clive” was his birth name. As a child, however, he adopted the nickname “Jacks,” which remained important to his friends and family.

Lewis later became a literary scholar, Christian writer, novelist, and broadcaster. His initials appear on works ranging from The Chronicles of Narnia to Mere Christianity. Readers sometimes assume that “C.S.” represents two first names, partly because initials were common in author names of his period. In Lewis’s case, the initials conceal the less familiar given name Clive and the family name Staples.

His formal name is therefore useful biographical context: the author known worldwide as C.S. Lewis was born Clive Staples Lewis, not “Charles” or “Christopher” Lewis.