During the First Barons’ War in 1216, King John of England was on the move as rebel barons challenged his rule. With him was a convoy carrying the king’s goods and valuables, including his royal regalia. As John and his entourage attempted to cross the Wash, a wide tidal estuary on England’s east coast, conditions quickly turned dangerous. The muddy tidal flats filled with water and the ground began to collapse under the carts and horses. 

Much of the baggage train was lost to the tides, and with it, various royal treasures including, according to most reports, the king’s crown.

The loss was another blow to John’s already maligned reputation. He was deeply disliked after years of heavy taxation used to fund failed military campaigns, leading to the loss of England’s territories in France. His authority was widely questioned across the country, and the loss of valuable royal property only intensified the image of a hapless monarchy struggling to stay in control. John died just days after the incident, likely from dysentery, and his reign was remembered as one of instability and misfortune.

Today, the lure of King John’s lost treasure persists, and amateur historians and treasure hunters are still drawn to the Wash in search of what was swept away centuries ago.