In 1271, through a marriage of his sister with Giovanni Visconti, judge of Gallura, he allied himself with the Visconti, the leaders of the Guelphs in Pisa.
Pada tahun 1271, melalui sebuah pernikahan saudarinya dengan Giovanni Visconti, Giudice Gallura, ia bersekutu dengan Visconti, para pemimpin Guelph di Pisa.