AN EXTRAORDINARY royal “jumble sale” of weaponry, oil portraits, silverware and vases owned by five kings of England was overshadowed yesterday by a feud between the pugnacious princes of the House of Hanover.

Unearthed from dusty basements and cobwebbed attics of a remote fairytale castle in northern Germany, 20,000 collectors’ items and artworks will go under the hammer in the next ten days in what is being billed as one of Europe’s most spectacular house sales.

Sotheby’s is running the auction at Castle Marienburg and is expecting to raise more than €13 million (£9 million) on behalf of the family of Prince Ernst August of Hanover, a cousin of the Queen.

More than 6,000 potential bidders — Russian millionaires and Californian interior decorators among them — have been winding their way through the long corridors of Marienburg ticking off targeted items, from a pair of St Petersburg vases (guide price €750,000) to seven 19th-century buckets (guide price €100). “A flea market for the super-rich” is how one art critic described the sale.

Prince Ernst August, famed for his marriage to Princess Caroline of Monaco and his scrapes with paparazzi photo-graphers, hopes to raise enough to preserve his other family estates in Germany. But his younger brother, Heinrich, has condemned the sale in an emotional outburst on television. “I am speechless,” he said. “This is a total sell-out.”

The entire legacy of the House of Hanover, a dynasty that provided more than a century of English kings, from George I to William IV, was about to be dismantled, the 44-year-old Prince said. “My brother does not understand tradition. He wants to make a killing out of this to finance a comfortable life abroad.”

Prince Ernst August, 51, refused to comment. But his sons, 19 and 22, who technically own the Marienburg treasure trove, insisted in a message to coincide with the opening of the auction that the money was needed to keep Marienburg and a palace in Hanover-Herrenhausen open to the public and “maintain our heritage for future generations”.

The sale has encountered other problems. Police have barred the sale of some 19th-century weapons because they have not been registered under German gun laws. “Since the most recent of the guns was made in 1865, there was not much chance of them being used in a bank raid,” an auction organiser complained.

Even so, 25 guns have been removed from the sale at short notice. The arms and armour are among the highlights of the sale — described by Sotheby’s as the most important group of weaponry to come on the market in living memory — and some of the suits of armour have been in the family since the 16th century.

Both professional and casual collectors seem to be interested in the dinner services and the silver because all of it is crested. A set of 380 18th-century English royal silver plates reveals something about the Hanover- ian love of entertainment at the English and German courts. Most German noble families have melted down some of their silver over the centuries to pay for soldiers or servants.

Another token of the Hanoverian love of food is a huge waistcoat, chest size 56 inches, that belonged to King George IV in the 1830s. The guide price is between €800 and €1,000.

“It’s a completely fairytale castle, a neo-Gothic fantasy,” said Marcus Linell, a Sotheby’s sales expert. “It was the sort of place where you clamber up the ivy to kiss the princess.”

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