Milan/Sforza Francesco Sforza (1401–1466) became Duke of Milan in 1450. (See the List of Characters.)
Naples/King of Spain Ferdinand (1452–1516) had originally agreed to divide the Italian kingdom of Naples with Louis XII of France, but Ferdinand drove out the French forces and took over Naples in 1503.
Duke of Ferrara actually two dukes, Ercole d'Este (1431–1505), who lost territory to the Venetians in 1484, and his successor, Alfonso d'Este (1476–1534), who managed to stay in power despite the opposition of three different popes. The d'Este family had ruled Ferrara for almost four centuries.
