Now it can be told: a huge scandal involving the disappearance of valuable royal goods, coteries of gay courtiers, drunken parties, inquiries that lead nowhere and a cover-up at the very highest level.
And all this is on a scale big enough to rock the monarchy and appal the citizenry, with an amazing cast of characters, some of whom end up disgraced, in prison or meeting sudden mysterious ends.
It all happened in the Ireland of 1907, when Edward VII went ballistic after somebody stole the Irish Crown Jewels from Dublin Castle. The extraordinary details of the theft, and the facts that the jewels have never been recovered and the culprits never found, have given rise to a rich crop of theories about what really happened.
Last night, RTE, the Irish state television station, aired a documentary on the topic, which suggested investigations into the theft had been pursued with less than maximum vigour. One theory is that the King hastily ended inquiries after being informed of a homosexual network based at the castle, which included Frank Shackleton, the disreputable brother of the polar explorer Ernest Shackleton, and the Duke of Argyll, the King's brother-in-law, who had a known fondness for Guardsmen.
The King, though himself no model of marital rectitude, had seen the German monarchy damaged by a homosexual scandal and certainly would have wanted things hushed up. He reportedly declared: "I will not have a scandal. I will not have mud stirred up and thrown about - the matter must be dropped."
The historian Owen Dudley Edwards commented in last night's programme, The Strange Case of the Irish Crown Jewels: "The very same people who may condemn homosexuality - maybe if not necking themselves with attractive footmen in the conservatory - may certainly be on the very best of terms with people whom they know are."
The Irish Crown Jewels consisted of a star and a badge encrusted with diamonds, emeralds and rubies. They had great symbolic value, as well as being worth millions at today's prices.
They went missing on the eve of a visit to Dublin by the King in 1907. No doors or locks were forced during the burglary, indicating an inside job.
A Scotland Yard detective was brought in to investigate, but his reports have gone missing. Another inquiry laid the blame on the hapless Sir Arthur Vicars, Ulster King of Arms. He was blamed not because he had taken the gems but because he was responsible for their safety. He was dismissed, and years later killed by the IRA for entertaining British officers at his home in Co Kerry.
He always maintained his innocence, complaining in his will that he had been treated in an "outrageous way by the Government backed up by the late King Edward VII when they shielded the real culprit and thief, Francis Shackleton."
Shackleton, Vicars' assistant, remains the prime suspect. He was one of a number of homosexual residents and employees at the castle, some of whom had colourful pasts. There were said to be drunken parties on the premises, with decades of rumours of "unnatural vice" going on behind its well-guarded walls. One nationalist politician intent on emphasising British corruption, referred to it as "Sodom and Begorrah". The fact that Shackleton was a friend of the Duke of Argyll is one reason George VII may have been his protector. Certainly someone up there liked Shackleton: one official report was generally inconclusive but made a point of declaring his innocence.
Any protection ended after the King's death, with Shackleton sentenced to 15 months' hard labour for fraud. Some say the jewel theft was Frank's way of helping Ernest, who was short of money to finance his polar expedition.
Frank's friend Richard Gorges, also homosexual, is suspected of being the man who took the jewels. He was later jailed for the manslaughter of a policeman in London. Another suspect died when he accidentally shot himself in the chest with his shotgun while climbing over a fence.
Today, the Crown Jewels remain unrecovered. Some say they were offered for sale to the Irish government in 1927; some say they are buried somewhere in Ireland; others say they were discreetly returned and that some of them are worn today by Queen Elizabeth. The official assumption, outlined recently by Jeremy Bagwell Purefoy of the Central Chancery of the Orders of Knighthood, is that they were broken up and sold in the Netherlands.
But every decade or so, an anonymous phone call or letter arrives, and Irish police dig up a piece of land in search of them. Whatever the true fate of the jewels, the episode continues to provide a rich vein of royal and Irish folklore.
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