C.S. Lewis identified 1931 as the year he converted to Christianity after years of atheism and theism.
Lewis had returned to belief in God before 1931, but he later described his conversion to Christianity as taking place in stages. His friendships with Owen Barfield and J.R.R. Tolkien, along with sustained reading and reflection, influenced this intellectual and spiritual development.
In Surprised by Joy, Lewis described himself as becoming a Christian in 1931. He became one of the twentieth century’s most influential Christian writers, producing works such as Mere Christianity, The Problem of Pain, and The Screwtape Letters.
A common oversimplification is to treat his journey as a single sudden event. Lewis’s own accounts distinguish between accepting theism and later embracing Christianity. The year 1931 refers to the Christian conversion he publicly described, not the beginning of every stage of his religious change.