Reportedly a descendant of the legendary Eraclea (after whom the town near Venice is named), he was elected by the assembly of the nobles after the deposition of his predecessor, Otto Orseolo.

Because the Orseoli had created so many links between their family and the hereditary ruling dynasties of Europe, various actions were taken against Venice as a retaliation for deposing Otto Orseolo.

He tried to obtain from the Holy Roman Emperor, Conrad II, a renewal of Venetian commercial privileges that had been granted to them by Otto III, but he was not able to do so.

In 1032, Pietro Barbolano abdicated under heavy pressure and Otto Orseolo was called back to rule from his exile in Constantinople.

Barbolano's successor was chosen in 1032 to be the wealthy merchant Domenico Flabanico, who had few noble ties, to spite the idea of creating a royal family in Venice.