1434

1434 (MCDXXXIV) was a common year starting on Friday of the Julian calendar, the 1434th year of the Common Era (CE) and Anno Domini (AD) designations, the 434th year of the 2nd millennium, the 34th year of the 15th century, and the 5th year of the 1430s decade. As of the start of 1434, the Gregorian calendar was 9 days ahead of the Julian calendar, which was the dominant calendar of the time.

• April 14, The foundation stone of Cathedral St. Peter and St. Paul in Nantes, France was laid.
• May 30, Battle of Lipany in the Hussite Wars
• Jan van Eyck paints the wedding of Giovanni Arnolfini
• Explorer Gil Eanes reaches Cape Bojador in Western Sahara. In the same year, Portuguese traders deliver their first cargo of African slaves to Lisbon.
• Zara Yaqob becomes Emperor of Ethiopia

• March 19 – Ashikaga Yoshikatsu, Japanese shogun (died 1443)
• September 23 – Yolande of Valois, Duchess of Savoy (died 1478)
  • probable
  • Matteo Maria Boiardo, Italian poet (approximate date; died 1494)
  • Kano Masanobu, Japanese painter (died 1530)

• 30 May
  • Prokop the Great, Hussite general (b. 1380)
  • Yuri IV, Russian grand prince (b. 1374)
• June 11 – King Wladislaus II of Poland
• June 19 – Alexandra of Lithuania, Duchess of Masovia
• November 12 – King Louis III of Naples (b. 1403)
• date unknown
  • John I, Duke of Bourbon (b. 1381)
  • Amda Iyasus, Emperor of Ethiopia