Which 1955 autobiography did C.S. Lewis write about his spiritual conversion?

Surprised by Joy is C.S. Lewis’s 1955 autobiography about his intellectual and spiritual development. The book traces his childhood, education, literary influences, military service, and eventual conversion to Christianity.

The title refers to Lewis’s idea of “joy,” a sudden longing or desire that he experienced through literature, imagination, and nature. He connected this feeling with writers such as George MacDonald and with his changing understanding of faith. The autobiography does not present conversion as one isolated moment; instead, it describes a gradual movement from atheism toward belief.

Lewis became a committed Christian in the early 1930s. His friendship with J.R.R. Tolkien and other Christian writers helped shape his thinking, although his religious development involved many influences. Surprised by Joy is therefore both a personal memoir and an account of the ideas that later informed his apologetic works and fiction.