1399

1399 (MCCCXCIX) was a common year starting on Wednesday in the Julian calendar.

 Events 
 February 3 – death of John of Gaunt, 1st Duke of Lancaster
 September 30 – Accession of Henry IV of England
 October 13 – Coronation of Henry IV of England
 November 1 – Accession of John VI, Duke of Brittany

Deaths
 February 3 – death of John of Gaunt, 1st Duke of Lancaster