J.R.R. Tolkien’s academic specialty at Oxford was Anglo-Saxon.
In 1925, Tolkien became Rawlinson and Bosworth Professor of Anglo-Saxon at the University of Oxford. The title referred to the Old English language and literature of early medieval England. His scholarship examined texts, vocabulary, manuscript traditions, and the historical setting of works such as Beowulf.
He later held the Merton Professorship of English Language and Literature from 1945 until his retirement in 1959. His academic work strongly influenced his fiction: Old English words, Germanic legends, heroic poetry, and medieval narrative structures appear throughout his invented histories.
Anglo-Saxon in this academic context means the study of Old English and the culture associated with early England. It does not mean that Tolkien’s university post was primarily archaeology or modern English creative writing. His language expertise helped him construct believable names, histories, and relationships among the peoples of Middle-earth.