The paper is devoted to reading the chronicle of Gallus Anonymus in the light of human-animal relations. My presentation will look at the animal metaphor of power and predatory rulership of Prince Boleslaw III the Wrymouth from the perspective of posthumanist anthropology. The research questions concern what type of zoon politikon Boleslaw III was (and Piast rulers in general), how he acquired such traits, and what this “animalization” of the Wrymouth tells us about political culture in 12th-century Poland. And what the animal nature of Boleslaw III tells us about his conflict with Prince Zbigniew and the dynastic crisis of the 1110s.