Bogomils

The Bogomils were a dualist Christian sect that emerged in the First Bulgarian Empire in the 10th century, teaching that the material world was created by a fallen, evil deity, while the spiritual world was the creation of a good God. Their doctrines, which rejected many orthodox sacraments, the veneration of icons, and the authority of the established church, spread across the Balkans and into Western Europe, where they influenced the Cathars and other movements. By the 14th century, the name "Bogomil" had become a generic term of abuse, used by the Inquisition and orthodox polemicists to tar any heretical group with the brush of extreme, foreign, and sexually depraved beliefs.

Conflation with Other Heresies

In the world of the abbey, the Bogomils are not a distinct, present group but a rhetorical category. During a heated debate with the abbot, William of Baskerville is accused of conflating different heresies, and the abbot lists the Bogomils alongside the Cathars, Patarines, and Waldensians as all being essentially the same evil. The abbot declares, "They are, they are because they are heretics," and specifically links them to the "ordo Bulgariae" and the "ordo Drygonthie," using the Bogomil name to suggest a chain of contamination from the East. This conflation is a deliberate strategy of the Inquisition, which William later explains to Adso: the simple people who join heretical movements cannot distinguish between doctrines, and the inquisitors exploit this by attributing the crimes of one sect to another, creating a single, monstrous image of heresy.

Association with Sexual Depravity and Violence

The Bogomils are repeatedly invoked in connection with the most lurid accusations of sexual license and violent ritual. Ubertino of Casale, in his fervent condemnation of the Pseudo Apostles of Montefalco, claims they engaged in orgiastic rites and infanticide, and he explicitly links these practices to the Bogomils. He says, "These things were said, many centuries ago, by the Armenian bishops, about the sect of the Paulicians. And about the Bogomils." This association is used to paint all heretics as practitioners of unspeakable acts, a smear that William of Baskerville, with his experience as an inquisitor, knows is often a product of torture and the desire to please the interrogator. The abbot, in his argument with William, also accuses the Fraticelli of embracing "the Bogomil heresy of the ordo Bulgariae and the ordo Drygonthie," further cementing the Bogomil name as a shorthand for the most depraved and dangerous form of dissent.

Narrative and Thematic Significance

The Bogomils function in the novel as a symbol of the church's inability—and unwillingness—to distinguish between different forms of dissent. The name is used not to describe a real, present threat but to create a monstrous Other against which orthodoxy can define itself. William of Baskerville's frustration with this conflation is central to his character: he argues that the simple people who join heretical movements are driven by hope and despair, not by subtle theology, and that the church's strategy of lumping all heresies together is a form of intellectual and moral laziness that leads to the burning of the innocent. The Bogomils, as a distant, foreign, and terrifying legend, thus become a key element in the novel's critique of institutional power and its manipulation of fear.