What academic subject did J.R.R. Tolkien teach at Oxford from 1925?

From 1925, J.R.R. Tolkien taught Anglo-Saxon at Oxford University.

He became Rawlinson and Bosworth Professor of Anglo-Saxon at Pembroke College, Oxford, succeeding Joseph Wright in the post. The subject, now commonly called Old English studies, concerns the language and literature of early medieval England. Tolkien held the chair until 1945.

His academic work was closely connected with his creative writing. He was a specialist in historical languages, philology, and medieval texts, and his teaching included the poem Beowulf. His 1936 lecture “Beowulf: The Monsters and the Critics” became an influential reassessment of the poem’s artistic importance.

Tolkien later became Merton Professor of English Language and Literature at Oxford. That later position is sometimes confused with his earlier chair. His expertise in Old English, Old Norse, Welsh, Finnish, and other languages helped shape the invented languages and historical depth of Middle-earth.