Northern Italian noble family. Muzio Attendolo, its founder; b. in the village of Cotignola in the Romagna, 1369; d. 1424, in the river Pescara, attempting to save the life of a page. As a boy he joined a band of mercenaries and later served under the condottiere Alberico da Barbiano, who gave him the name of Sforza, adopted by his descendants. As a leader of mercenary troops and a shrewd soldier he acquired wealth and fame. Several of his numerous illegitimate sons founded princely houses. Most famous among them was Francesco, first of the Sforza dukes of Milan; b. 1401; d. 1466. A condottiere like his father, he married (1441) Bianca Maria Visconti, illegitimate daughter of Filippo Maria, last Visconti duke of Milan (d. 1447). Francesco claimed his state and succeeded him in 1450. An outstanding statesman, he played an important role in Italian politics, concentrating on the maintenance of peace and order in his territories. Humanists at his court included Filelfo and Decembrio.
Among his more than 30 legitimate and illegitimate children, the following were outstanding. Ascanio Maria, legitimate; b. 1455; d. Rome, 1505. He became a cardinal in 1484 and held many benefices, including the bishopric of Pavia. A partisan of Cardinal Roderigo Borgia, he supported his election as Pope alexander vi in 1492 and helped to bring about the marriage of Lucrezia Borgia, the Pope's daughter, with his own nephew Giovanni Sforza di Pesaro. A worldly prelate involved in politics, he kept a brilliant court in his Roman palace, Ippolita Maria, legitimate; b. 1445; d. 1488. She married Alfonso, Duke of Calabria, in 1465. Educated by humanists, she was famous for her learning and the fine library she collected. Sforza Secondo, illegitimate; b. 1435; d. 1491; founded the collateral branch of Sforza di Borgonovo. Francesco's successor as duke of Milan was his oldest legitimate son, Galeazzo Maria; b. 1447; who was assassinated by three youths for personal motives in 1476. Galeazzo's children included Bianca Maria, legitimate; b. 1472; d. 1510; who was married to the Emperor Maximilian I in 1493. Caterina, illegitimate; b. c. 1463; d. 1509; was famous for her involvement in politics and military affairs. Descendants of her marriage to Girolamo Riario (1477), the nephew of Pope sixtus iv, were the princes Riario-Sforza. Her third husband, Giovanni di Pierfrancesco de'Medici, was the ancestor of the grand dukes of Tuscany. Galeazzo Maria left as his heir his son Gian Galeazzo; b. 1469; d. 1494. After a short regency by his mother, Bona of Savoy, and her adviser Cicco Simonetta, the rule of Milan was usurped in 1478 by Ludovico il Moro; b. 1452; d. 1508; legitimate son of Francesco, and uncle of the young duke. As regent and, after the death of Gian Galeazzo (1494), as duke of Milan, he kept a brilliant court and was famous as patron of the arts. His appeal to King Charles VIII of France in 1494 led to the French invasion of Italy and to his ultimate defeat. He died in a French prison in Loches. Ludovico's two sons ruled Milan for a brief time. Massimiliano; b. 1493; d. 1530; was duke from 1512 to 1515. His brother Francesco II; b. 1495; d. 1535; reigned from 1521 until his death under the supervision of the Spanish, to whom Milan fell in 1535.
Other branches of the Sforza family founded by illegitimate sons of Muzio Attendolo were the Sforza di Santafiora, descended from Bosio; b. 1411; d. 1476; and the Sforza di Pesaro, going back to Alessandro; b. 1409; d.1473. A third branch, the Sforza di Caravaggio, descended from Giampaolo; b. 1497; d. 1535; illegitimate son of Ludovico il Moro.
Bibliography: g. b. picotti et al., Enciclopedia Italiana di scienzi littere ed arti, 36 v. (Rome 1929–39) 31:5711–577. c. m. ady, A History of Milan under the Sforza, ed. e. armstrong (London 1907). l. collison-morley, The Story of the Sforzas (New York 1934). n. valeri, L'Italia nell'età dei principati, dal 1343 al 1516 (Milan 1949). Storia di Milano (Milan 1953–) v.7–8, for bibliog. g. peyronnet, "Il ducato di Milano sotto Francesco Sforza (1450–1466): Politica interna, vita economica e sociale," Archivio-storico italiano 116 (1958) 36–53.
[e. g. gleason]