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Remains of the Mary Rose in the museum

What caused the Mary Rose to sink?  The most popular theories

Image: Remains of the Mary Rose in the Mary Rose Museum | CC BY-SA 4.0

The Mary Rose was Henry VIII’s favourite warship. A formidable warrior of the sea, she sailed for over three decades and fought in countless battles. But on 19th July 1545, during a confrontation with the French off the coast of Portsmouth, the Mary Rose began to sink and no-one is certain why.

Henry VIII’s favourite ship

The King looked on as approximately 80 of his vessels took on around 150 French gallies in the Solent. It was a calm day, so the French attackers chose to row in as their sails would have been next to useless in those conditions. However, some theories suggest that an unexpected gust of wind caused the Mary Rose to topple.

It’s reported that as Henry VIII listened to the shouts of the 470 men on board, he said: ‘Oh, my gentlemen. Oh, my gallant, gallant men.’ Most of the men on the Mary Rose were trapped beneath the anti-boarding netting that was supposed to stop enemies from gaining access to the ship. However, it also stopped people from leaving. Only 34 survived.


In the new series of Ross Kemp: Deep Sea Treasure Hunter, Ross Kemp was given special permission to dive on the site of the shipwreck and to bring any items that were at risk of further degradation to the surface. Could these items offer any clues to explain why the great ship sank beneath the waves?

One of the most popular theories speculates that the Mary Rose took damage from French opposition on her starboard side. This would have led to her taking on water pretty quickly before going under.

Strong tidal currents

Most of the ship’s port side has been eroded away by the strong tidal waves and sea termites over the centuries. However, the starboard side remained well preserved as it was buried in thick silty mud. Most of this half of the ship was raised in 1982, but the bow castle remains covered. Scientists are still striving to unveil it as it could definitively tell us how much damage the Mary Rose took on the day she sank.

Another theory suggests that Henry VIII may have played a major role in the downfall of his flagship. He was insistent on having as many guns as possible at the front of his ships and historians have obtained a letter that proves the king wanted two new bronze guns at the head of the Mary Rose. These alterations would have weakened and destabilised the ship’s structure making it more susceptible to large gusts of wind.

Neil Brock, Ross Kemp and Mallory Haas inspect a piece of wood retrieved from the site of the Mary Rose shipwreck
Neil Brock, Ross Kemp and Mallory Haas inspect a piece of wood retrieved from the site of the Mary Rose shipwreck 

Diving the Mary Rose

As Ross prepared to dive into the Solent, one of the UK’s busiest shipping lanes, he met Chris Dobbs, an original member of the dive team that first discovered the Mary Rose. Chris first dived on the site in 1979 and it’s been his life’s work to educate the world about this part of history.

It is a great privilege for Ross to dive on this wreck as only a handful of people have been allowed: filming is even more rare. He begins by exploring the area where the starboard side once lay and heads towards where he thinks the bow might be. While underwater, Ross and his dive partner, Mallory Haas, make a few discoveries that they believe could be significant. This included a couple of pieces of wood buried into the seabed that could potentially be part of the Mary Rose’s bow castle, as well as some broken pottery.

Historic finds

Once back on the surface, the finds were analysed to see where they came from. Due to its shape, condition and the fact that it looked very similar to other pieces of timber retrieved from the site, it’s very likely that Ross Kemp found a part of the Mary Rose. In fact, three months later after further scientific testing and analysis, the Mary Rose Trust added the wood and the pottery to its collection.

Before leaving Portsmouth, Ross took some time to learn more about the people who sailed on the Mary Rose. Some historians have put the sinking down to human error, blaming both the captain and the crew. It’s been suggested that Sir George Carew was unfamiliar with the capabilities of the ship and gave an order that led to disaster. On the other hand, others believe the crew were unruly and ignored the orders of their captain.

Whatever the circumstances of the sinking, the large and diverse crew all played their part in the success of the English navy. Almost 10,000 bones and bone fragments have been recovered from the wreck site, representing at least 179 individuals. Most of these sailors originated in the UK, but many others came from across Europe and even as far as North Africa.

While there is still a long way to go to work out what happened to the Mary Rose in her final hours, the new finds from Ross and his team have kept alive the hope that the mystery will one day be solved.

Ross Kemp: Deep Sea Treasure Hunter starts Easter Monday at 9pm on Sky HISTORY.