The House of Riario, sometimes referred to as Riario-Sforza, is an Italian noble family from Savona, near Genoa.

Closely associated with the Papal States, the family gained control over several signorie ("lordships"), such as Bologna and Forlì.

The war caused the cession of Rovigo from Ferrara to Venice, but the Papal States did not obtain any territory.

Eventually he was murdered by the rival House of Orsi in 1488, and his wife Caterina became regent for his son Ottaviano Riario (1479–1523).

In 1499 Pope Alexander VI, member of the strong House of Borgia, created the title of "Duke of Romagna" (uniting the lordships of Forlì, Imola, Faenza, Cesena, Ravenna and Rimini) for his illegitimate son Cesare Borgia, and the Riario family removed first to Bologna, then also to Rome and Naples.