Tynwald Day is the National Day of the Isle of Man, usually observed on 5 July (if this is a Saturday or Sunday, then on the following Monday).
It was originally a celebration of the island's legislature, the High Court of Tynwald, a legacy of the Scandinavian conquest of the Isle of Man back in the Middle Ages.
Since 2000, the week of Tynwald Day has been commemorated as Manx National Week. Cultural events are held throughout the week; at the conclusion, the Manx national anthem is played, and a fireworks display is staged.