Which 1939 lecture by J.R.R. Tolkien discussed the value and nature of fairy stories?

J.R.R. Tolkien’s 1939 lecture about the value and nature of fairy stories was titled On Fairy-Stories. He delivered it as the Andrew Lang Lecture at the University of St Andrews in Scotland.

The essay argues that fairy stories deserve serious attention rather than being treated merely as children’s entertainment. Tolkien discusses their settings, their relationship to imagination, and what he calls recovery, escape, and consolation. He also explains his idea of the “eucatastrophe,” a sudden joyful turn that produces a satisfying happy ending.

On Fairy-Stories became one of Tolkien’s most influential statements about fantasy. It is often read alongside his creative work because it helps explain why he valued invented worlds, mythic storytelling, and moral transformation. The essay was later published in revised form, and its arguments influenced later writers and scholars of fantasy literature.