Historian under fire for ‘Nazi Prince’ claims

Martin Allen, author of a number of controversial Second World War history books - one of which claimed the Duke of Windsor (pictured with his wife Wallis Simpson and Hitler) was a Nazi traitor, another that Churchill ordered the assassination of SS chief Heinrich Himmler - is facing some tough questions about his source material after it was revealed that the documents he used to support his claims are forgeries.

More disturbingly, it is now known that the documents used by Allen had all been planted in the National Archives, the public records office which holds the written records of the British state going back 800 years.

One of the archivists, Louise Atherton, says Allen "relied heavily" on forged files and accused him of "significant" exaggeration and inaccurate quotation.

Allen was unavailable yesterday, but one of his former literary agents, Robert Smith, said that Allen had previously denied any involvement in the forgeries.

One of the books in question, Hidden Agenda: How the Duke of Windsor Betrayed the Allies accused the Queen's uncle of helping the Germans to conquer France, a claim that garnered considerable publicity in 2000.

In 2003 Allen published The Hitler/Hess Deception, which argued that the flight of Hitler's deputy, Rudolf Hess, in 1941 was part of a plot to oust Churchill. Once again, Allen was challenging the standard version of events, and using documents to prove his thesis.

Another book, Himmler's Secret War, cited documents from the National Archives that purported to show that British agents acting on Churchill's orders murdered Himmler, the head of the SS, in 1945. This contradicted accepted accounts that Himmler had killed himself.

Max Hastings, the journalist and Second World War historian, told the Sunday Times: "It is hard to imagine actions more damaging to the cause of preserving the nation's heritage than wilfully forging documents designed to alter our historical record."