Gian Galeazzo Visconti (November 1351 - September 3, 1402), son of Galeazzo II Visconti and Bianca di Savoia, was the first Duke of Milan (1395) 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. Wikipedia
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