At which university did J.R.R. Tolkien teach when he wrote much of his Middle-earth fiction?

J.R.R. Tolkien taught at the University of Oxford while writing much of his Middle-earth fiction.

Tolkien held several academic posts at Oxford. He was a professor of Anglo-Saxon from 1925 to 1945 and later the Merton Professor of English Language and Literature from 1945 until 1959. His academic work focused especially on languages, philology, and medieval literature.

Oxford was not merely Tolkien’s workplace. He lived and worked in the city for decades, and his scholarly interests in Old English, Old Norse, Welsh, Finnish, and other languages fed his invented languages and fictional histories. He also belonged to literary discussion groups, including the Inklings, whose members met at Oxford.

Tolkien’s academic career and fantasy writing overlapped. The Hobbit was published during his Oxford years, and The Lord of the Rings was largely written and revised while he remained connected with the university.