How Adolf Hitler held the German people in thrall to the disastrous degree that he did is a question that has intrigued historian and television producer Laurence Rees for much of his career. He talks to AP Maginness about his new book and accompanying television series The Dark Charisma of Adolf Hitler: Leading Millions into the Abyss FROM an unremarkable early adulthood Adolf Hitler transformed himself into one of the most powerful leaders the world has seen.
In doing so he also led one of Europe's most advanced nations to the edge of destruction.
But how did someone very much considered an oddball as a young man transform himself into the absolute leader of the German people?
It's a question that has been nagging English historian and television producer Laurence Rees through more than 20 years of writing about and documenting the Nazis.
"When I met people who were Nazis I was always coming back to the key question of how Hitler did what he did. How was it that he was so extraordinarily persuasive?" Rees (55) says.
Rees has worked on numerous documentaries exploring differing facets of the Nazi regime - he wrote and directed The Nazis: A Warning from History (1997), Horror in the East (2001) and Auschwitz: The Nazis and the Final Solution (2005), all of which were made for the BBC.
"Many of the people whom I met and had had contact with Hitler talked about his remarkable charisma. This fascinated me for years," Rees says.
His new book, The Dark Charisma of Adolf Hitler: Leading Millions into the Abyss, is an examination of the man and the mind and was published earlier this month. A three-part BBC2 television series will be screened next Monday at 9pm (November 12).
"One of my first questions was to ask what is charisma?" Rees says.
"I began thinking about my wife. We met while we were at university and as soon as I met her I was immediately taken with her. Eventually we married.
"A few years later I met a university friend and on hearing whom I had married he said, 'Hmm, I think I might have been at a few parties with her'.
"I thought, 'surely he would have remembered more of her than that?'
"But she had no effect on him, so why did she have such a big effect on me?"
So Rees compared his wife to Hitler?
"It made me think that when we talk about charisma we are talking as much about ourselves as the effect other people have on us," he says.
"With Hitler it is as much to do with the people he meets as with Hitler's own charisma.
"There is a dual connection - people felt an emotional connection with him."
Rees expands this idea to the German people, their emotional psyche and how Hitler connected with these emotions.
"There is a point where he begins to change and it is relatively late on in his life. The creature you get at 24 is not remotely remarkable or charismatic. It is after this period that things start to change.
"When Hitler begins making an impression on people it is because he speaks to the predispositions that the German people have after the First World War.
"He is well aware of the suffering of the German people because he too suffered the humiliation and horrors of the war.
"He understands the [post-First World War] reparations, the French occupation and the losses. He uses these experiences to connect with people because he knows them as well as anyone else."
Hitler was a war hero who received the Iron Cross for bravery, a decoration rarely awarded to someone of Hitler's low military rank - he was a corporal in the First World War - and social status.
"If you read his letters from this period you begin to realise that he is extremely idealistic but then things begin to change," Rees says.
"He starts seeing things in terms of a Darwinian struggle - we are all animals and the weak will die.
"There is a fundamental battle of humanity. You have to be strong enough to take things for yourself, that is the only moral code."
Hitler also knew that to portray himself as a hero would be tapping into a deep cultural vein.
"The Germans were prone to this sort of hero. Their history and culture are full of these types. Bismarck is one. It is prominent in the works of Nietzsche and Wagner and goes back much further in folk literature."
However, Rees does not believe that what happened in Germany could only have happened to the Germans.
"I don't buy that it is only the Germans who could have carried out the Holocaust, very similar things happened elsewhere," he says.
"You have to remember that this type of thing happened in lots of other places. Just look at what the Ustase in Croatia during the Second World War."
Other traits in Hitler's personality also proved useful during his rise to power, even his use of the German language.
"It is rare for Hitler to refer to anyone using the informal 'Du', he always uses 'Sie', the formal," Rees says.
"One person he does refer to as Du is Rohm but then he has him killed.
"He doesn't have planning meetings or ask anyone for advice. With this comes an incredible power.
"All these traits combine to make him aloof and therefore, from a distance at least, strong."
Crucially though, Rees points out, Hitler also possessed a pragmatic streak.
"For example, he loathes Christianity but is very careful at various points not to go too far with this publicly," he says.
Hitler's dark charisma helped him to come to the fore in what were extremely dark times for the German people, creating the perfect storm that eventually led millions into the abyss.
■ The Dark Charisma of Hitler - Leading Millions into the Abyss by Laurence Rees is out now published by Ebury priced £25 (hardback). The three-part series The Dark Charisma of Hitler begins on BBC2, Monday at 9pm. ■ ■ TRANSFORMATION:: From an unremarkable early adulthood Adolf Hitler transformed himself into one of the most powerful and destructive leaders the world has seen ■ ■ AUTHOR:: Laurence Rees has worked on numerous books and programmes exploring different facets of the Nazi regime