Peter I of Arborea

Who was Peter I of Arborea?

Peter I, of the Serra family, was the eldest son and successor of Barisone II of Arborea, reigning from 1186 to his death. His mother was Barisone's first wife, Pellegrina de Lacon. He was crowned King of Sardinia, the title his father had used, with the support of a majority of the Arborean nobility.

Immediately after his father's death, he was opposed by his nephew Hugh, the son of Hugh I of Bas and Ispella, Peter's half-sister, the elder daughter of Barisone by his second wife, the Catalan Agalbursa. Agalbursa had the support of Alfonso II of Aragon, but she died soon after instigating the war between her grandson and Peter. Peter was supported by the Republic of Pisa, while Hugh had the backing of the Republic of Genoa. In 1189, however, Peter made peace with Genoa and swore fealty to the Republic salva domini pape fidelitate. In 1192, a compromise was finally reached at Oristano whereby Arborea was divided between Peter and Hugh.

In the late 1190s, Constantine II of Logudoro and his son Comita III, allies of Genoa, warred with Peter, who was under the protection of William I of Cagliari.