Cannobio is a town and comune on Lago Maggiore in Piedmont, Italy. The local inhabitants probably became subject to Roman rule by the time of the emperor Augustus. Sarcophagi from the 2nd-3rd century CE have been found and conserved in the "Palazzo della Ragione".
Cannobio was named as a village by 1207, and was granted administrative autonomy. The Palazzo della Ragione was constructed by 1291 under the government of the podestà Ugolino da Mandello.
Cannobio was assigned to the archdiocese of Milan and from 1817 was under the authority of the bishop of Novara. Its "pieve" comprised the areas of Cannobina, Cannero, Brissago and several areas on the eastern side of the lake. The church of St. Vittore, already present in 1076, and with a bell tower from the 13th century, was completely rebuilt between 1733 and 1749.