What was C.S. Lewis's academic specialty at Oxford before his Cambridge professorship?

C.S. Lewis’s academic specialty at Oxford was English literature.

Lewis taught English at Magdalen College, Oxford, from 1925 until 1954. His scholarship concentrated particularly on medieval and Renaissance literature, periods that also informed his fiction and Christian apologetics. He became a Fellow of Magdalen in 1929.

His academic career followed an unusual path. After studying at University College, Oxford, Lewis achieved a first in Honour Moderations, a first in Greats, and a first in English. He was also a tutor in philosophy at University College before securing his Oxford English post.

In 1954 he moved to Cambridge as professor of medieval and Renaissance literature. This later appointment explains why Lewis is associated with both universities, but Oxford was the principal setting of his earlier teaching career and the place where he developed many of his best-known ideas.