The daughter of the Prince of Capua, she got married in 999 with
Sergio III, the grand-son of Mansone I, but this was only a marriage
of convenience and political interests.
Maria was very interested in the political facts of the region and, in order to back up her brother’s wish of territorial expansion, she organized a coup d’état in 1028 against her husband, who voluntary chose exile in Byzantium. As a consequence, Maria proclaimed herself "Ducissa e Patricissa", and ruled together with her son Mansone II. After a few months the other son Giovanni, who, on the other hand, already ruled alongside with his father, thinking that he was entitled to have the dukedom, started a long fratricide war.
Maria came to an agreement with Giovanni.
Mansone was blinded and shut in a tower (Torre del Gallo Lungo). Such a cruel act against Mansone touched the feelings of Amalfi people who, filled with indignation, rebelled against the perpetrators of the crime.
Nothing else is known about Maria, who almost disappeared in the darkness of history.