The Nonexistent Knight is set during the final years of the reign of Charlemagne, the founder of the Carolingian Empire who united large parts of Western Europe under his rule. By the time the novel takes place, however, Charlemagne is not what he once was. Age has caught up to the ruler, who is disinterred in and bemused by the empire he has founded. In the opening scene, he must be introduced to his own paladins as he marches off to yet another war. Charlemagne, victor of many battles, is more interested in a flock of ducks in a roadside pond than the impending battle. His cognitive decline means that he struggles to remember much, while his vast achievements mean that he has very little motivation to continue his conquering. Charlemagne has won so much and so often, that he has lost any desire to repeat his own unrepeatable glories. He marches into battle on muscle memory, even if he does not know his own commanders. Charlemagne’s decline is suggestive of the end of an era, both the leader and society itself disinterested and perfunctory.

The decline of Charlemagne is indicative of a decline in everything which he represents.