Owain Glyndŵr Day
Owain Glyndŵr Day is held on September 16. Celebrates the life of Owain Glyndŵr who became Prince of Wales on this day in 1400. This event in the second decade of the month September is annual. 
Help us
Help us 
Owain Glyndwr was the last native Welsh person to hold the title Prince of Wales. He was born in 1359 into a powerful family of the Anglo-Welsh nobility, during a time of relative peace between the tribes of Wales and the English aristocracy. Prince of Wales is a title historically used by independent Welsh princes and since the 14th century by the heir apparent to the English and later British throne.
He led a rebellion against the king. The rebellion started because the English king failed to support him when a neighbour stole some of his land. He established the first Welsh parliament at Machynlleth.
When Owain Glyndŵr died, no one ever discovered his hiding place or where he was buried. Fun fact: Owain Glyndŵr translates in English to “Owen of the Glen of Dee Water.”
September 16th is the anniversary of the proclamation in 1400, of Owain Glyndŵr as Prince of Wales and is now celebrated annually as Owain Glyndŵr Day. In more recent times, the 16th September has become an unofficial holiday in Wales.
Similar holidays and events, festivals and interesting facts
Battle of Britain Day on September 15 (United Kingdom);
National Gyoza Day in United Kingdom on September 20
European Myeloma Day on September 27
World Marmite Day on September 28
National Coffee Day on September 29
The Archangels Michael, Gabriel, and Raphael Day for England and Ireland on September 29 (this is christian feast day and one of the four quarter days in the Irish calendar);
World Copywriter's Day on September 30