"Gian Galeazzo Visconti (16 October 1351 – 3 September 1402), son of Galeazzo II Visconti and Bianca of Savoy, was the first Duke of Milan (1395) and ruled the late-medieval city just before the dawn of the Renaissance. He was the founding patron of the Certosa di Pavia, completing the Visconti Castle at Pavia begun by his father and furthering work on the Duomo of Milan." - (en.wikipedia.org 17.11.2019)
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