Year 1421 (MCDXXI) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar.
February 2 – Yongle Emperor, the third emperor of Ming Dynasty shifted the Ming capital from Nanjing to Beijing.
March 21 – Battle of Baugé: A small French force surprises and defeats a smaller English force under Thomas, Duke of Clarence, a brother of Henry V of England, in Normandy.
May 26 – Mehmed I, Sultan of the Ottoman Empire, dies and is succeeded by his son Murad II.
November 17–November 19 – St. Elizabeth's flood: The coastal area near Dordrecht in the Netherlands is flooded due to the extremely high tide of the North Sea; 72 villages are drowned, killing about 10,000 people.
John III of Dampierre, Marquis of Namur, sells his estates to Philip the Good, Duke of Burgundy.
The first patent is issued by the Republic of Florence.
Portuguese sailors sent by Henry the Navigator cross the Cape Non, going as far as the Cape Bojador.
Traditional date – Foundation of Larabanga Mosque in modern-day northern Ghana.
The Ming dynasty possibly discovered the Americas, according to amateur historian Gavin Menzies in his book 1421: The Year China Discovered America, although this claim is largely disputed.
March 9 – Francesco Sassetti, Italian banker (d. 1490)
May 29 – Charles, Prince of Viana (d. 1461)
June 3 – Giovanni di Cosimo de' Medici, Italian noble (d. 1463)
July 25 – Henry Percy, 3rd Earl of Northumberland, English politician (d. 1461)
August 1 – Thomas Dutton, medieval English knight (d. 1459)
October 10 – John Paston, English politician (d. 1466)
December 6 – King Henry VI of England (d. 1471)
date unknown
Sōgi, Buddhist priest and Japanese poet (died 1502)
Agnès Sorel, mistress of Charles VII of France
Ponhea Yat, ruler of the Khmer Empire (died 1467)
January 10 – Niccolò I Trinci, lord of Foligno (assassinated)
March 22 – Thomas of Lancaster, 1st Duke of Clarence, second son of Henry IV of England (killed in battle) (born 1388)
April 21 – John FitzAlan, 13th Earl of Arundel (born 1385)
May – Balša III, ruler of Zeta
May 26 – Mehmed I, Ottoman Sultan (b. 1389)
1421 Wikipedia (Text) CC BY-SA