Born in 1401

Mar 27 Albert III Duke of Bavaria the Pious of Bavaria-Munich , since 1438 Duke of Bavaria-Munich. He was born in Munich to Ernest, Duke of Bavaria and Elisabetta Visconti, daughter of Bernabò Visconti
May 12 Emperor Shōkō the 101st emperor of Japan, according to the traditional order of succession. His reign spanned the years from 1412 through 1428
Jul 23 Francesco I Sforza an Italian condottiero, the founder of the Sforza dynasty in Milan, Italy. He was the brother of Alessandro, with whom he often fought
Aug 16 Jacqueline Countess of Hainaut Duchess of Bavaria-Straubing, Countess of Holland and Zeeland and Countess of Hainaut from 1417 to 1433. She was also Dauphine of France for a short time between 1415 and 1417 and Duchess of Gloucester in the 1420s, if her marriage to Humphrey, Duke of Gloucester, is accepted as valid
Sep 14 Maria of Castile Queen of Aragon Queen consort of Aragon and Naples as the spouse of Alfonso V of Aragon. Maria acted as the regent of Aragon during the reign of her spouse, as he was absent during most of his reign; her regencies lasted between 1420 and 1423 and between 1432 and 1458. She was also briefly Princess of Asturias in her own right as the heiress presumptive to the throne of Castile
Oct 27 Catherine of Valois the Queen consort of England from 1420 until 1422. She was the daughter of Charles VI of France, wife of Henry V of England, mother of Henry VI of England, and through her secret marriage with Owen Tudor, the grandmother of Henry VII of England. Catherine's older sister Isabella was queen of England from 1396 until 1399, as the child bride of Richard II
Nov 26 Henry Beaufort 2nd Earl of Somerset the eldest son of John Beaufort, 1st Earl of Somerset, and the grandson of John of Gaunt, 1st Duke of Lancaster and Katherine Swynford.
Dec 21 Masaccio the first great Italian painter of the Quattrocento period of the Italian Renaissance. According to Vasari, Masaccio was the best painter of his generation because of his skill at recreating lifelike figures and movements as well as a convincing sense of three-dimensionality. Masaccio died at twenty-six and little is known about the exact circumstances of his death