Gian Galeazzo Visconti (November 1351 – September 3, 1402), son of Galeazzo II Visconti and Bianca di Savoia, was the first Duke of Milan (1395)[1] and ruled the late-medieval city just before the dawn of the Renaissance. He was the great founding patron of the Certosa di Pavia, completing at Pavia the palazzo begun by his father and furthering work on the Duomo of Milan. Although most famous as Signore of Milan, Gian Galeazzo was born into the branch of the Visconti that possessed the signoria of the city of Pavia. In 1385 Gian Galeazzo gained control of Milan by overthrowing his uncle Bernabò through treacherous means. His first marriage was to Isabelle de Valois, who brought him the title of comte de Vertus in Champagne, rendered in Italian as Conte di Virtù, the title by which he was known in his early career.[2]A devoted father to his daughter Valentina (wife of Louis, Duke of Orleans and mother of the famous poet, Charles of Orleans), Gian Galeazzo reacted to gossip about Valentina at the French Court by threatening to declare war on France. Galeazzo's role as a statesman also took other forms. Soon after seizing Milan he took Verona, Vicenza, and Padua, establishing himself as Signore of each, and soon controlled almost the entire valley of the Po. He lost Padua in 1390, when it reverted to Francesco Novello Carrara. He received the title of Duke of Milan from Wenceslaus, King of the Romans in 1395 for 100,000 florins. Gian Galeazzo had dreams of uniting all of northern Italy into one kingdom,a revived Lombard empire. The obstacles to his success included Bologna and especially Florence. In 1402 Gian Galeazzo launched assaults upon these cities. The warfare was extremely costly on both sides, but it was universally believed the Milanese would emerge victorious. The Florentine leaders, especially Coluccio Salutati worked successfully to rally the people of Florence, but the Florentines were being taxed hard by famine, disease, and poverty. Galeazzo won another victory over the Bolognese at the Battle of Casalecchio on June 26, 1402. Galeazzo's dreams were to come to naught, however, as he succumbed to a fever at the castello of Melegnano in August 10, 1402. He died on September 3. His empire fragmented as infighting among his successors wracked Milan, partly through his division of his lands among both legitimate and illegitimate heirs.[3] Gian Galeazzo was a complicated man. He spent 300.000 golden florins in attempting to turn from their courses the Mincio from Mantua and the Brenta from Padua, in order to render those cities helpless before the force of his arms. His library, housed in the grandest princely dwelling in Italy, the castello in Pavia, was renowned, and his rich collection of manuscripts, many of them the fruits of his conquests.