C.S. Lewis became a Christian in 1931.
Lewis’s religious development was gradual rather than a single early-life event. He had returned to belief in God by 1929, influenced partly by conversations with friends including J.R.R. Tolkien and Hugo Dyson. In September 1931, he described a further movement from theism to Christianity.
Lewis later recalled that he had been reluctant to accept Christianity, despite growing evidence that the Christian worldview made intellectual and imaginative sense to him. His conversion transformed the direction of his writing. He became one of the twentieth century’s most influential Christian apologists and wrote works including The Problem of Pain, Mere Christianity, and The Four Loves.
Dates connected with Lewis’s conversion are sometimes presented too simply because he described several stages of belief. The year 1931 refers to his conversion to Christianity, while 1929 is associated with his earlier acceptance of theism.