The island was frequented since Roman times. In 1220, St. Francis landed here at his return from the Holy Land during the Fifth Crusade, and founded a hermitage here. After his death, the island was given to the Minorites by the Venetian patrician Jacopo Michiel, a relative of the patriarch of Grado, Angelo Barozzi, to found a convent.
During the Austrian rule of Venice the island, abandoned due to its unhealthy characteristics, was used as a powder depot. In 1858 it was donated to the diocese of Venice, who allowed the friars to refound a convent here.