In its fundamental conception, as well as in many of the significant details of its working out, Lord of the Rings is heavily indebted to G. K. Chesterton’s now little read poem of 1911, The Ballad of the White Horse.
The major theme of both works is the war and eventual victory, despite all odds, of an alliance of good folk against vastly more powerful forces of evil, and the return of a king to his rightful state. Like Lord of the Rings, Chesterton’s poem is set in a heroic society after the decay of a highly civilized imperial power — in England, that is to say, in the aftermath of the Roman Empire. (Tolkien’s Minas Tirith, built on seven levels, greatly resembles a medieval idealization of Rome.) King Alfred, its hero,is fighting a losing war to save his kingdom from complete conquest by the Danes. As one would expect with Chesterton, it is a war of white against black, of Christianity against a diabolical paganism that has defeated Rome and is now trying to make all good men its slaves. … The enemy is not simply Danes, or barbarians in general, but a wholly malignant and almost irresistible force that stands behind all the enemies of Christianity: This power blights everything it touches — there are repeated references to its distorting effects even on the natural world — and the men who serve it become like Tolkien’s Orcs. … To fight against this menace, Alfred, hiding in exile, summons three kindreds of free, Christian peoples as allies. Alfred himself, like Tolkien’s Aragorn, is an idealized heroic figure who roams around in humble disguise and is sometimes mistreated by the ignorant. Instead of Dwarves, Elves, and Men of Numenorean descent, he leads an alliance of Saxons, Celts, and Romans.