Dorset family's Jolly Roger flag from HMS Unbroken up for auction

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The rare flag, which has come from a Weymouth family, is going under the hammer at The Tank Museum, in Bovington in a militaria auction organised by Duke’s of Dorchester on May 14.

The book 'Unbroken, the story of a submarine' dedicated to Petty Officer Sharp by the author and sub's captain, which is to go under the hammer at The Tank Museum in a Duke's of Dorchester sale. The photos include one with the crew

The tradition of creating Jolly Roger flags on submarines began during the First World War after First Sea Lord Admiral Sir Arthur Wilson claimed the vessels were 'underhanded, unfair and damned un-English', adding the crews ought to be hanged as pirates.

The tradition continued during the Second World War and now these flags are incredibly rare with the one on sale offered with an estimate of up to £10,000.

Julian Smith, the militaria expert at Duke’s of Dorchester, said: "This is an astonishing war relic that has come direct from a family who live in Weymouth.

"The Jolly Roger flags were created by the submariners to keep a record of their successes – and they were flown from the boats.

"HMS Unbroken spent most of the war in the Mediterranean where she caused havoc for the enemy.

"She also attacked a railway line on the Italian mainland but suffered damage by return fire and had to be repaired in Malta."

The Jolly Roger flag made on HMS Unbroken in WWII that is going under the hammer at a Duke's sale to be held at The Tank Museum in Bovington, Dorset.

Interpreting the flag shows that HMS Unbroken sank four merchant ships with the deck gun as well as sending ten others and two warships to the seabed.

She also completed four 'cloak and dagger' operations which included dropping off Captain Peter Churchill DSO in Antibes, France, in 1941.

He returned that evening with a French resistance leader, Francois d’Astier de La Vigerie – codename ‘Bernard’ – who was then taken to England.

‘Bernard’ went on to support General Eisenhower in preparations for the invasion of France.

In 1942 Unbroken again dropped off Churchill in France; he was by this time a member of the Special Operations Executive (SOE).

With him was Edward Zeff, a wireless operator whose job it was to assist the French resistance.

Fred Sharp was fortunate to survive the war because before joining Unbroken he was drafted from three submarines before they were sunk.

Unbroken, a U-class sub, was launched in 1941 and went to join the 10th Flotilla in the Mediterranean.

In 1944 she was loaned to the Soviets who returned her in 1949 and the following year Unbroken was broken up.

Mr Smith added: "Dropping off saboteurs and picking them up from occupied France was a high-risk act of derring-do but under her captain, Lt Cdr Alastair Mars DSO, DSC and Bar, she prevailed.

"Churchill and Zeff who were inserted into France were both later captured, tortured and sent to concentration camps – but astonishingly both survived, even Jewish Zeff.

"Peter Churchill's exploits were later portrayed by Trevor Howard in the 1950 film 'Odette'.

"The sale also includes a book about the history of HMS Unbroken written by her captain, Lt Cdr Mars, which he dedicated to Weymouth-man Petty Officer Sharp."

Gordon Sharp, Fred’s grandson, said: "My grandfather didn’t talk about the war and it was only around 15 years ago after he died that we found out what he had done.

"He was the one who actually made the Jolly Roger flag, which was the reason he got to keep it. He just used bits of material on board to create it.

"After the war he ran a pub in the Wyke Regis, which was fittingly called The Mermaid.

"He was a man who enjoyed socialising, loved a whisky and his family was extremely important to him.

"We now feel the time is right to sell these items and hope perhaps it might be bought by a museum."

The sale also includes other superb lots including a DSO group of medals that belonged to Lt Col Henry Pleydell-Railston of the 1st Rifle Brigade.

His heroic actions at Hannebeck in May 1915 were immortalised in the book 'Deeds that Thrill the Empire'.

Also under the hammer is the collection of the late Lance Corporal Dennis Jones, which includes a variety of helmets, uniforms, bayonets, headdresses, a military Land Rover and a B31 motorbike.

The collection also includes a 'Green Goddess', a military fire engine in impeccable condition.

Rosanna Dean, the Tank Museum manager said: "We’re pleased to be hosting our second militaria auction with Duke’s, who are offering a unique set of items for a military enthusiast audience.

"As with our exhibits it is the stories that surround the items that fascinate and intrigue us – and they remind us of the heroism and sacrifice of those who served."