C.S. Lewis became a Christian in 1931 after an earlier period of atheism.
Lewis had described himself as an atheist for part of his young adulthood, although his views developed over time. Conversations with colleagues and friends, including J.R.R. Tolkien and Hugo Dyson, contributed to his renewed consideration of Christianity. Lewis later described his conversion as a movement from atheism to belief in God and then to Christianity.
He became a theist in 1930 and converted to Christianity in 1931. His account of this intellectual and spiritual development appears in Surprised by Joy, his autobiography published in 1955.
Lewis’s conversion should not be confused with a single public event or denomination change. It was a gradual process involving philosophy, literature, personal reflection, and conversations with other Christian thinkers.