The first son of
Muzio Attendolo Sforza,
Francesco I Sforza, married
Bianca Maria Visconti (1425–1468) in 1441. She was the daughter and only heir of the last
Duke of Milan,
Filippo Maria Visconti. The Sforza held Pesaro until 1512, after the death of
Costanzo II Sforza. Muzio's third son, Bosio (1411–1476), founded the branch of
Santa Fiora, who held the title of count of
Cotignola; the Sforza ruled the small
county of Santa Fiora in southern
Tuscany until 1624. Members of this family also held important ecclesiastical and political positions in the
Papal States, and moved to Rome in 1674, taking the name of Sforza Cesarini. The Sforza became allied with the
Borgia family through the
arranged marriage (1493–1497) between
Lucrezia Borgia and
Giovanni (the illegitimate son of
Costanzo I of Pesaro). This alliance failed, as the Borgia family annulled the marriage once the Sforza family were no longer needed. In 1499, in the course of the
Italian Wars, the army of
Louis XII of France took Milan from
Ludovico Sforza (known as
Ludovico il Moro, famous for taking
Leonardo da Vinci into his service). After Imperial German troops drove out the French,
Maximilian Sforza, son of Ludovico, became Duke of Milan (1512–1515) until the French returned under
Francis I of France and imprisoned him. In 1521
Charles V drove out the French and restored the younger son of Ludovico, Francesco II Sforza to the duchy. Francesco remained the ruler of Milan until his death in 1535 and as he was childless the Duchy reverted to the Emperor, who passed it to his son
Philip II in 1540, thus beginning the period of Spanish rule in Milan. ==Sforza rulers of the Duchy of Milan==