The Siege of Damietta in 1249 begins with an improbable victory and turns into a lesson in how zeal can overrule judgment. Louis IX lands despite the threatening Egyptian shore, and the Templars follow him into defeat because their ideal of knighthood binds them to the crusade. In a different register, the episode’s later importance lies in the novel’s scrutiny of claims to hidden history: the Colonel’s certainty about a supposed Templar message reproduces the same passage from evidence to conviction.

The Landing and the Crusading Ideal

Louis IX attacks Damietta from the sea. The shore appears bristling with pikes, halberds, banners, shields, and scimitars; Joinville nevertheless describes the armed men as splendid, their golden weapons catching the sun. Louis could wait, but chooses to land. He tells his followers that unity in charity will make them invincible, and that defeat will make them martyrs while victory magnifies God’s glory. The Templars do not share his confidence, yet they have been trained to embody the ideal of the knight and follow the king into what the narration calls his mystical madness.

The landing succeeds, and the Saracens abandon Damietta. Louis hesitates to enter, fearing treachery, but the city is undefended and its treasures and hundred mosques are within reach. He converts the mosques into churches. The apparent triumph immediately poses a strategic choice: march toward Alexandria, which would deprive Egypt of a vital port, or toward Cairo, the heart of the country. Robert d’Artois urges the more ambitious march on Cairo, driven by hunger for glory. The Templars, initially cautious, become eager for action.

From Victory to Disaster

Louis orders his forces to avoid isolated skirmishes, but the Marshal of the Temple ignores the prohibition when he sees a squadron of the sultan’s Mamelukes. He calls the knights to attack in God’s name rather than endure what he regards as a shame. That impulsive charge embodies the tension between discipline and the order’s self-image: the Templars are meant to follow the king’s crusade, yet their conception of honor can propel them beyond his commands.

The Saracens establish themselves beyond the river near Mansura. The French attempt to build a dam and make a ford, shielding the work with mobile towers. Their opponents use Greek fire, learned from the Byzantines: a barrel-like projectile with a long, spear-shaped tail, hurled like a flying dragon. At night its brightness makes the Christian camp visible as if it were day. The account thus moves from the spectacle of the sun glinting on weapons at the landing to a weapon whose fire illuminates the camp in darkness, while the campaign’s advance meets a prepared and technologically capable enemy.

The Text’s Later Echo

The siege is narrated as part of a wider reflection on the Templars’ frustrated crusading purpose. Even in Joinville’s day, Louis IX persists in believing another crusade is worth attempting, and the Templars remain willing to follow him: without a crusade, the narration observes, they could not justify the Temple. Their loyalty is therefore both vocation and vulnerability. The ideals that give the order meaning also draw it into a campaign where religious conviction, ambition, and military judgment pull in different directions.

Centuries later, the Colonel presents a supposed coded text to Casaubon and Belbo, insisting that Ingolf’s transcription is the original because he sees no way the truth could be otherwise. He identifies a demoniacal-looking litany, then claims that a method associated with Trithemius reveals the phrase “Les 36 inuisibles separez en six bandes.” His account depends not only on a proposed cipher but also on assumptions about the Templars, secret knowledge, and the text’s provenance. Much later, the French sentence is reconsidered as a phrase associated with seventeenth-century Rosicrucian writing; the possibility that Ingolf encoded the Provins message himself reverses the Colonel’s historical conclusion. The siege’s later resonance is therefore not that it proves a continuous secret tradition, but that the novel places crusading certainty beside modern interpretive certainty, showing how a compelling pattern can outrun what the evidence establishes.