What was the name of Tolkien’s 1938 lecture that became a landmark essay on fantasy?

Tolkien’s 1938 lecture was titled On Fairy-Stories.

Tolkien delivered the Andrew Lang lecture at the University of St Andrews in 1938. The lecture was later revised and published as an essay, becoming one of his most influential statements about fantasy, fairy tales, and imaginative literature.

In the essay, Tolkien discusses the functions of fairy stories, including recovery, escape, and consolation. He also develops the idea of “secondary worlds,” imagined realms that can possess their own internal consistency and truth. These arguments helped establish fantasy as a serious literary subject rather than merely children’s entertainment.

The essay is often read alongside Tolkien’s fiction, but it is not a plot summary or a guide to Middle-earth. The title is also sometimes confused with The Monsters and the Critics, another major Tolkien lecture, delivered in 1936 and focused on Beowulf scholarship.