Which author influenced C.S. Lewis's conversion through conversations about myth?

J.R.R. Tolkien influenced C.S. Lewis's conversion through conversations about myth and Christianity.

Lewis and Tolkien were colleagues at Oxford and members of the literary group known as the Inklings. Their discussions included mythology, language, literature, and the relationship between pagan myths and Christian belief. Lewis had already moved from atheism toward belief in God before becoming a Christian; Tolkien’s arguments helped shape the later stage of that journey.

Lewis later described a conversation with Tolkien and Hugo Dyson in September 1931 as especially important. The discussion concerned the idea that the Christian story could be understood as the “true myth,” fulfilling themes found in earlier myths while being grounded in historical claims.

Tolkien did not single-handedly convert Lewis, and Lewis’s intellectual development involved several other friends, books, and experiences. Owen Barfield was also a major influence. The precise answer is Tolkien because he was the author and close colleague associated with the myth-focused conversations remembered in accounts of Lewis’s conversion.