Son of the Doge Pietro Fregoso, and Bartolomea Grimaldi, daughter of Giovanni, lord of Monaco, Menton and Roccabruna, he was called Battistino, to distinguish him from his paternal grandfather.

[2] From the court of Piombino, he moved to Novi Ligure, a fief granted by the Duke of Milan to his father in return for his military aid.

In 1478, taking advantage of the turbulent situation of Genoa, torn by continuous threats of a civil war between the oligarchic factions, he left Novi with a good number of armed men and, having arrived in Genoa, he acquired with corruption the favor of Obietto Fieschi, with the help of the army of these, was able to forcefully dismiss the doge in charge Prospero Adorno.

Recalled at home by Paolo Fregoso's opponents, he did not manage to regain the title of doge, despite the fall of his uncle in 1488.

Reinstated in his possessions by Ludovico Sforza, with whom he had ambiguous relations, negotiating between the Duke of Milan and the King of France, he never returned to his fiefdoms.