Died in 1404

Apr 27 Philip the Bold Duke of Burgundy and jure uxoris Count of Flanders , Artois and Burgundy. The fourth and youngest son of King John II of France and his wife, Bonne of Luxembourg, Philip was the founder of the Burgundian branch of the House of Valois
Sep 2 Pierre II Count of Alençon the son of Charles II of Alençon and Maria de la Cerda. He was Count of Alençon from 1361 until his death in 1404 and Count of Perche from 1377 until his death in 1404
Sep 14 Albert IV Duke of Austria a Duke of Austria.
Sep 27 William of Wykeham Bishop of Winchester and Chancellor of England. He founded New College Oxford and New College School in 1379, and founded Winchester College in 1382. He was also the clerk of works when much of Windsor Castle was built
Oct 1 Pope Boniface IX Pope from 2 November 1389 to his death in 1404. He was the second Roman Pope of the Western Schism. During this time the Antipopes Clement VII and Benedict XIII continued to hold court as pope in Avignon under the protection of the French monarchy
Oct 15 Marie of Valois Duchess of Bar the sixth child and second daughter of John II of France and Bonne of Bohemia.
Oct 17 Caterina Visconti a member of the Italian noble family Visconti, which ruled Milan from 1277 to 1447. She was the second wife of Gian Galeazzo Visconti, the first Duke of Milan, and was the mother of two succeeding Dukes of Milan, Gian Maria and Filippo Maria Visconti. Her granddaughter was Bianca Maria Visconti, who became Duchess of Milan in 1447. Caterina served as Regent of Milan from 1402 to 1404, during her elder son's minority, but due to Gian Maria's suspicion of her alleged treason , he had his mother arrested and imprisoned in the castle of Monza, where she was presumably poisoned in 1404
Dec 13 Albert I Duke of Bavaria a feudal ruler of the counties of Holland, Hainaut, and Zeeland in the Low Countries. Additionally, he held a portion of the Bavarian province of Straubing, his Bavarian ducal line's appanage and seat