One of the most important literary precedents to The Two Towers is the Old English epic of Beowulf, which Tolkien translated and taught at Oxford. Several scenes in both works mirror each other to the extent that Tolkien's borrowings become obvious to one who knows both works well.

Moreover, the overall themes of loyalty to king, courage under arms, and persistence in the face of what may appear to be an unchallengeable doom all appear in both works.

The legends of King Arthur as revised and recorded by Sir Thomas Malory and others also resemble The Two Towers in many ways. Like the Arthurian legends, Tolkien's work details not only martial contests, but the political maneuvering of allies both true and false in the pursuit of justice.

Frodo and Sam resemble in many ways the Grail Knight, whether he be Sir Gawain or another, who must...