In 1447, when Giano was elected doge, he held diplomatic positions in the court of Alfonso V of Aragon at Naples and in Rome.

Here, Pope Nicholas V (also of Ligurian origins) appointed him as Lord of Corsica after the island had been completely subjugated to Genoa with the papal approval.

In September 1450, he abdicated in favor of his cousin Pietro di Campofregoso, and moved to the fortress of Sarzanello near Sarzana.

In 1468 he ceded Sarzana to the Republic of Florence, causing, in the following years, numerous struggles between the Florentine and the Genoese for its possession.

Having become an admiral of Ferdinand II of Aragon, in 1478 he returned to Genoa at the head of a fleet of seven galleys to help free the city from Gian Galeazzo Sforza's domination.