Pope Honorius III, enemy of the Pisans, immediately sent his chaplain Bartolomeo to annul the marriage, but he failed and the pact between Pisa and Logudoro stood.
In 1237, Pope Gregory IX sent his chaplain Alexander to Torres to receive recognition from Adelasia of papal suzerainty over Logudoro, as well as the lands she inherited from her grandfather William of Cagliari, in Pisa, Massa, and Corsica.
At the palace of Ardara, in the presence of the Camaldolese abbot and monks of S. Trinità di Saccargia, she made the oath of vassalage and Ubaldo affirmed it, giving over the castle of Monte Acuto to the bishop of Ampurias as a guarantee of his good faith.
At that time, the Doria family of Genoa, Pisa's main rival, convinced the Emperor Frederick II to marry his bastard son Enzo to Adelasia and create a Kingdom of Sardinia.
Sassari expelled its Pisan governor with the support of the Doria, refortified its defences, and adopted a republican model of government in alliance with Genoa, which sent an annual podestà.