On this day in 1216, English King John, also known as John Lackland, allegedly lost the Crown Jewels while passing through a marshy area in East Anglia. Namely, the wagons in which the jewels were being transported passed through a route which was only usable at low tide. However, the wagons were too slow to avoid the rapidly rising tide, so that many were caught and lost in the flood. It seems the king himself used a safer route and thus managed to avoid disaster.
The place where the jewels were was located near Sutton Bridge in what is now the county of Cambridgeshire. It is not widely known that the eastern coast of England used to be very marshy, sometimes even completely flooded (salt marshes), so that the sea sometimes reached almost as far as Cambridge. It was a similar phenomenon to the one in the Netherlands, which are in fact situated on the opposite coast of the North Sea.
The Crown Jewels have not been found until this day, despite several attempts using the newest available methods. King John was the younger brother of the famous King Richard the Lionheart, and is known from the stories about Robin Hood because he governed England while his brother was away on a crusade in the Holy Land. King John died only one week after losing the Crown Jewels, having caught dysentery. He died in Newark Castle in Nottinghamshire, and was succeeded by his 9-year-old son Henry III.