Year 1400 (MCD) was a common year starting on Wednesday of the Gregorian calendar and a leap year starting on Thursday (link will display the full calendar) of the Julian calendar. The year 1400 was not a leap year in the Proleptic Gregorian calendar. Events January–December Henry IV of England quells the Epiphany Rising and executes the Earls of Kent, Huntingdon and Salisbury, and the Baron le Despencer, for their attempt to have Richard II restored as king. February – Henry Percy (Hotspur) leads English incursions into Scotland. February 14 – The deposed Richard II of England dies by means unknown in Pontefract Castle. It is likely that King Henry IV ordered his death by starvation, to prevent further uprisings. March 23 – Five-year-old Trần Thiếu Đế is forced to abdicate as ruler of Đại Việt (modern-day Vietnam), in favour of his maternal grandfather and court official Hồ Quý Ly, ending the Trần Dynasty after 175 years and starting the Hồ Dynasty. Hồ Quý Ly subsequently changes the country's name to Đại Ngu. May – Frederick I, Duke of Brunswick-Lüneburg is declared as a rival to Wenceslaus, King of the Romans. However, Frederick is murdered shortly after. August The English occupy Edinburgh in Scotland, but fail to capture Edinburgh Castle. The princes of the German states vote to depose Wenceslaus as King of the Romans, due to his weak leadership and mental illnesses. August 21 – Rupert, Count Palatine of the Rhine, is elected as King of the Romans. September 16 – Owain Glyndŵr is proclaimed Prince of Wales by his followers, and begins attacking English strongholds in northeast Wales. October/November – Sack of Aleppo (1400) during Timur's conquest of Syria. December – Manuel II Palaiologos becomes the only Byzantine Emperor ever to visit England. Date unknown Timur defeats both the Ottoman Empire and the Mamluk Sultanate of Egypt, to capture the city of Damascus in present-day Syria. Much of the city's inhabitants are subsequently massacred by Timur's troops. Timur conquers the Empire of The Black Sheep Turkomans, in present-day Azerbaijan, and the Jalayirid Dynasty in present-day Iraq. Black Sheep ruler Qara Yusuf and Jalayirid Sultan Ahmad flee, and take refuge with the Ottoman Sultan Bayezid I. In modern-day Korea, King Jeongjong of Joseon abdicates in fear of an attack by his ambitious younger brother, Taejong. Taejong succeeds to the throne. Prince Parameswara establishes the Malacca Sultanate, in present-day western