Background
Born c. 1460 as the fourth son of Roberto Sanseverino d"Aragona, first count of Caiazzo (1418-1487), who was the son of Elisa Sforza, sister of duke Francesco Sforza, the duke of Milan.
Born c. 1460 as the fourth son of Roberto Sanseverino d"Aragona, first count of Caiazzo (1418-1487), who was the son of Elisa Sforza, sister of duke Francesco Sforza, the duke of Milan.
He was taught by master-at-arms and scholar Pietro del Monte (1457-1509) and befriended Leonardo da Vinci (who lived in his house in Milan). Bianca died six years later, in 1496, from an "affliction of the stomach", while Galeazzo was away campaigning. Leading the forces of Ludovico Sforza, he succeeds in tying up the duke of Orléans following the Battle of Fornoue He is made a knight of the Order of Saint Michael in 1494 on a visit to Lyon.
He then went to Innsbruck to the court of emperor Maximilian I, following the court to Nuremberg in 1499, where he befriends Albrecht Dürer.
He accompanies Francis I of France on his encounter with Henry VIII of England at Calais in 1520. He is made count of Martigues in 1522.
In the service of France, Galeazzo campaigned in the Italian Wars from 1509 until his death in the battle of Pavia in 1525, where the French cavalry was decimated by a force of 1,500 Basque arquebusiers.