A document vital to the capture of top Nazi Heinrich Himmler has been unearthed in the UK 75 years after his death. The items belonging to the SS leader, found in the possessions of a judge, are now due to go on display.

On 22 May 1945, a trio of odd-looking men were spotted by a patrol near a checkpoint in Bremervörde, northern Germany.

It was just a few weeks after World War Two had ended but many Nazis were still at large and there were fears some may try and regroup or escape.

Two of the men, wearing smart long green overcoats, were walking ahead of a third man. The trailing figure, sporting an eye patch, looked broken and dishevelled. The pair in front kept glancing back as if to make sure he was still there.

They were taken to a checkpoint where British soldiers asked to see their papers. They handed over the A4-sized identity document German soldiers were given at the end of the conflict which listed their name, rank, date of birth and other information. The third man’s papers said he was a sergeant named Heinrich Hizinger.

He must have hoped that the document and his lowly rank would mean he would pass through checkpoints. He was wrong.

On the document was an official stamp and British military intelligence had seen the same stamp and unit details being used by members of the SS who had been trying to flee. And so word had gone out that anyone else with those details was to be detained.

Next morning, the three men were taken to a detention camp.

Once there, Hizinger asked to see a senior officer. Although his cover was still intact, he must have feared it would not last long and perhaps hoped he could bargain his way out of the situation. So he took off his eye patch and calmly revealed who he really was.

He was Heinrich Himmler, the man who had been head of the SS and a key architect of the Holocaust.

After Hitler’s death in his bunker, this made him one of the most-wanted Nazis still alive and a man responsible for many of the worst crimes of the Third Reich.

The British team began to question him to confirm he was who he said.

A few hours later a medical officer, Capt Wells, was told to check Himmler. As he came to look inside his mouth he saw a small blue-tipped object hidden in his cheek.

As Capt Wells tried to pull it out, Himmler struggled with the doctor, pulled his head away and crushed the object between his teeth. It was a cyanide capsule. He was dead within minutes.

Himmler had been given away by a fake stamp that his own people had placed in a document. The incriminating papers remained hidden for 75 years, but they can now be seen for the first time after being donated to the Military Intelligence Museum in Bedfordshire.

And alongside the papers are a slightly more bizarre item – the braces that Himmler was wearing when he was captured.

Souvenir-hunting was common and many of Himmler’s personal items were snapped up (one of the sergeants who carried out the original arrest got hold of Himmler’s slippers, someone else got his shaving foam and razor blades).

In the case of the documents, they were recently donated by the great niece of Lt Col Sidney Noakes.

Noakes, born in 1905, was a lawyer who joined the Intelligence Corps in 1943 but was seconded to MI5. Much of what he did at MI5 remains shrouded in secrecy, but after the war he returned to his career as a lawyer, eventually ending up a County Court Judge. He died in 1993.

So how did he end up with the papers?

Documents detailing the arrest say “a gentle interrogation” of Himmler by MI5 officers took place before the final medical examination. These officers, by convention, would not have been named, and so it is not certain who they were.

“The logical assumption is that he was one of the two MI5 interrogators,” says Bill Steadman, curator of the Military Intelligence Museum. “I can’t think of any other way he could have got them.”

He believes it is possible Noakes was given permission to keep the documents by his superiors once any intelligence value had been extracted.

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The objects stayed with Noakes and his family until they were recently donated and they will be on display once the museum reopens.

They are more than just a curiosity but also explain how a senior Nazi was caught.

“Without this damning stamp on the document it is possible that Himmler may have been able to pass through the system unnoticed, and escape as did many other wanted Nazis,” says Bill Steadman.

“What appeals to me most about this story is that the Germans themselves made his unmasking an absolute certainty.”