Crucial letters expected to cast light on the Queen Mother's attitude towards the biggest royal crisis of the 20th century were withdrawn at the last minute from a collection of official papers thrown open today.
Scholars and journalists gathered at the Bodleain library, Oxford to begin reading 11 boxes of papers left by the former royal confidant and government minister Sir Walter Monckton. But they discovered that one box is being held back and will remain sealed until 2037.
Earlier this week the historian Andrew Roberts forecast that the archive would reveal the true extent of the Queen Mother's involvement in the feud between the Duke of Windsor, who abdicated from the throne in 1936, and her husband, who became King George V1 in his stead.
Mr Roberts said the papers could also at last solve the enduring controversy over how deeply the duke sympathised with fascism. But today Mr Roberts said: "It would appear that the crown jewels are missing from this collection."
The Oxford constitutional expert Vernon Bogdanor said the papers disclosed today contained no spectacular revelations. "This is part of history and part of the British constitution," he said. "But it is also a personal family matter and a personal family wound. I don't believe the royal family want that wound constantly exposed."
One document was a telegram from the Queen Mother's brother-in-law, the late Duke of Windsor, to Adolf Hitler just before the second world war broke out, Prof Bogdanor said. Hitler replied by saying peace depended on England, not Germany. There was no evidence in the files of any "treasonable" activity by the duke.
"The archive shows there was no responsibility to remove the king from the throne. It was inevitable from the start. It shows the king was determined to act constitutionally throughout," he said.
Oxford university said the box was being kept closed in line with public record office policy. However, "all but a small number of papers" were being made available for research.
Mr Roberts said it appeared that one or two letters from the Queen Mother to Sir Walter had been weeded out of some of the boxes made available today.
He said one of the letters from the then queen to Sir Walter in August 1940 may have thrown light on the feud between Buckingham Palace and the Duke and Duchess of Windsor. He said the letter related to the arrival of the Duke and Duchess in the Bahamas where the former king was to become governor.
"This letter could be terribly exciting and a real insight into the extent of the personal feud between the then Queen and the Windsors. By the time that the Duke of Windsor was on his way to the Bahamas it became evident that there were people at the palace, though we do not know whom, who were trying to ensure that the Duchess did not get royal treatment," he said.
"This letter may have told us something about this."
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