Bonnie Prince Charlie, Louis XV and the lost ship that could have changed history

The fact that Louis XV left Charles Edward Stuart in hiding, without supplies, after his defeat at the Battle of Culloden in 1745 has long puzzled historians.

Now a team of divers believe they have found the key to the mystery – in the shape of a wreck of a ship, perhaps containing a vast quantity of gold, that sank en route to the prince.

Significantly, a rare ring seal of Mary, Queen of Scots, believed to have been carried by the crew as proof of their loyalty, was found in the area. Now an excavation is under way to find evidence that the ship was a supply vessel.

Records show Louis XV made one failed attempt to send relief ships, laden with huge quantities of gold coins, weapons and troops, to the Young Pretender, in hiding in the Scottish Islands. Those two vessels were intercepted by the Royal Navy and limped back to France with their precious cargoes.

There has been speculation the French king made further attempts to rekindle the rebellion, though what happened to any supply vessels has remained a mystery. But the diving team claims the wreck they found could lead to an entire chapter of history being rewritten if it surrenders a huge quantity of gold coins – showing it was a lost relief ship.

A professional diver, Kevin McCormack, uncovered a tiny copper disc at the site of the wreck off the Anglesey coast and experts have verified it is identical to the signet ring of Mary, Queen of Scots.

The seal was found in concretion – solidified wreckage – lifted from an area of coast near Porth Dafarch Beach in the 1980s.

However, it was only after Mr McCormack's father, Joe, also a diver, sent the disc to be examined at the National Museum of Scotland in Edinburgh that the historical possibility was recognised.

Joe McCormack said yesterday: "It's a historical fact that King Louis XV sent a number of ships laden with supplies to support Charlie while he was in hiding. Two of them were named 'Le Mars' and 'La Bellone', and they were laden with a huge quantity of gold and weapons.

"These two vessels never reached Charlie. They were intercepted and damaged in an encounter with the English navy, after which they limped back to France.

"We believe the wreck site we are working on is where another relief vessel sank without trace.

"The name of the vessel is not known, but evidence suggests it was probably a British-built sailing ship that had been captured, or bought, by a French privateer and provisioned to sneak up the coast unchallenged.

"Mary, Queen of Scots was Bonnie Prince Charlie's great-great-grandmother. Our theory is that the seal was a 'token of authenticity' carried by an emissary on the relief vessel to demonstrate his credentials on meeting the prince."

Historian Michael Fry said:

"If there had been more tangible French help, I have no doubt the clansmen would have fought on and perhaps changed the whole of Scottish history."

A 20-strong dive team led by Kevin McCormack and his company, Maritime Resurgence, now plan to explore the site.

George Dalgleish, principal curator of Scottish history at the National Museums, who examined the seal, could not specify its origins but warned it might be a Victorian copy of a ring in the British Museum.