Intelligence chiefs obtained evidence in early 1944 that Hitler was planning to turn Nazism into a worldwide secret society if Germany was defeated in war.
The evidence was held by C, the head of MI6, and was added to by German agents working for the Special Operations Executive, a separate branch of the intelligence services. Lord Selbourne, head of the SOE, wrote to Winston Churchill's closest aide, Sir Desmond Morton in May 1944, warning that every effort should be made to obtain the names of German youths passing through schools for a new "Hitler Leader Youth".
A report from an agent in central Germany, included in documents released today by the Public Record Office, said that boys aged between 13 and 17 were being given three hours' instruction a week on tasks to be done if Hitler were to hand over power.
These boys "would act in complete agreement with the Führer for the protection of the German people. There would certainly be some weak-kneed people who would allow themselves to be led away from the predetermined course of action. These people would have to be watched and carefully punished by the party," the agent reported.
Students would work in groups of five to "render such people harmless".
They would live close to each other, but would take orders from someone they had not met.
They were already being given practical instruction and discussing the merits of fulfilling their tasks with "pistols, poison or hangings".
Lord Selbourne said: "The boys who have been trained are sent away ... on some pretext or other and settled throughout Germany, where they can live unnoticed and can learn everything about local conditions.
"They are, of course, sworn to absolute secrecy, but since many of them are still, in fact, children, they have talked, even if perhaps only to their parents."
The reply from Sir Desmond revealed that MI6 believed the agent's report was true and had evidence of a much larger plot.
"It is exactly what the Nazis would do. C has evidence of the plans they are already making in other fields to turn Nazism into a secret society in case of defeat. Their plans are worldwide," he wrote.Reuse content