Before he became known as the author of The Hobbit and The Lord of the Rings, J R R Tolkien taught English language and literature at Oxford University. Back then, his area of expertise wasn’t yet Middle Earth but the medieval poem Beowulf, about a legendary hero who fights terrible monsters. Already interested in the fantastical, Tolkien had a Balrog-sized bone to pick with his fellow academics, who laboriously studied the historical and religious context of Beowulf’s epic quest without paying proper attention to the otherworldly creatures he encountered along the way. As Tolkien saw it, monsters like the giant Grendel didn’t distract from the text’s deeper meaning. They were its deeper meaning.

His argument, the academic Charity Urbanski explains in a new book, Medieval Monstrosity: Imagining the Monstrous in Medieval Europe, has become the foundation of contemporary monster theory, a theory that presents monsters not as figments of our own imagination but as reflections of collective anxieties.

Just as Tolkien’s nameless, hyper-militarised orcs have been interpreted as symbols of modernity and fascism, so do many medieval creatures reflect the troubles of the time periods in which they originated. Often, their original significance turns out to be completely different to their later one. Modern-day werewolves, as seen in