Genoa in 1547. This commercial center had gained its independence from France as well as a new prince through the actions of Andrea Doria 19 years previously. But the Doge Doria is now an old man 80 years old and there are fears that his nephew, Gianettino Doria, will be his successor. Among the Genoese nobility there is resistance to the rule of the Dorias and especially to his tyrannical nephew. A few of the dissatisfied rally around the strong-willed republican Verrina, but most have their own selfish goals. Sacco joins the conspiracy because he thinks he will be able to rid himself of his debts if there is a rebellion. Calcagno wants Fiesco’s wife Leonore. Bourgognino wants to finally marry his bride Bertha,Verrina’s daughter. Her seduction and rape by Gianettino Doria provide the immediate motive for the conspiracy.