Peter II (died 1241) was the Giudice ("Judge") of Arborea from 1221 to his death. He was also Peter IV, Viscount of Bas. He was "pious and submissive to the church" and his extensive "donations of privileges and judicial lands impoverished his state of glory." In 1221, Peter began ruling alone. In 1228, he allied with the Visconti of Gallura, then allied with Pisa. He was consequently attacked by William II of Cagliari and Marianus II of Torres. They desired to maintain a condominium in Arborea, but internal fighting allowed Peter to solidify his authority with little opposition.