C.S. Lewis became a Christian in 1931, after a prolonged intellectual and spiritual journey.
Lewis had returned to theism by 1930 and then moved toward Christianity through conversations and friendships with people including J.R.R. Tolkien and Hugo Dyson. He later described his conversion as a reluctant return to God, famously writing that he was “the most dejected and reluctant convert in England.”
The exact chronology is sometimes simplified. Lewis’s movement was not a single moment that can be reduced to one conversation: he first rejected Christianity in youth, recovered belief in God, and subsequently embraced Christianity. He joined the Church of England and soon became one of the twentieth century’s most influential Christian apologists.
His conversion preceded books such as The Pilgrim’s Regress, published in 1933, and the wartime broadcasts later adapted into Mere Christianity. Those works reflect the Christian outlook he had adopted by 1931.