Which C.S. Lewis memoir recounts his conversion from atheism to Christianity?

Surprised by Joy is the C.S. Lewis memoir that recounts his conversion from atheism to Christianity.

Published in 1955, Surprised by Joy describes Lewis’s intellectual and spiritual development, including his childhood imagination, friendships, reading, service in the First World War, and changing views about religion. The title refers to “joy,” a recurring longing that Lewis treated as an important clue in his spiritual life.

Lewis did not move directly from atheism to full Christian belief. He first became a theist and later returned to Christianity, influenced in part by conversations with friends such as J.R.R. Tolkien and Hugo Dyson. The memoir presents this journey selectively rather than as a complete day-by-day diary.

The book is often read alongside Lewis’s later apologetic works, but it is primarily an autobiography of intellectual and religious formation.