The Monastery of Sant’Ilario on the Venetian mainland, near Malcontenta, was founded in 819 by the doges Agnello and Giustiniano Partecipazio, and was a prominent place for much of the Middle Ages. It was abandoned in the early 1200s.
The war with the Franks, in 809, as recounted fancifully in the “Chronicon Altinate”.