Joncey's answer, below, falls short. Dietrich Bonhoeffer has not been canonized or recognized as a saint by the Roman Catholic Church. The Nazi regime and German RC came to an agreement (Reichskonkordat) that was recognized by the Pope in 1933. However, despite the konkordat, RCs, the RC church and priests were persecuted.
Hitler co-op'd the Protestant German church, creating a new national church and appointing a leader that was a fanatical Nazi. The Confessing Church was organized by major German theologians and leaders such as Karl Barth and Martin Niemoeller, but opposed the Nazi's control of the church more as oppression of the church by the state than oppression of Jews and Christians by the state.
Bonhoeffer was an early and persistent voice against the Nazis and their injustices. Bonhoeffer was jailed for participating in an effort to assassinate Hitler, and was executed by the Nazis in Feb. 1945. While he was a staunch opponent, he was one of a number of clergy and theologians who stood against the regime, and could not be called it's 'greatest foe'.
Dietrich Bonhoeffer would not then, not does he now qualify as a 'saint' because he opposed Hitler. The RC process -canonization- to be named a saint has steps which are detailed, rigorous, and rarely is a step or investigation waived. While Bonhoeffer is considered a martyr by many Christians for his stand against the Nazis, he is not recognized in any way by the RC church as a saint, nor, as a Protestant, is he likely to be.
Joncey's answer:<<Bonhoeffer became a saint, because he was part of a group of Christian denominations that joined together in an anti-Nazi alliance, called the "Confessing Church", which included Catholic denominations. During Hitler's regime, he was the greatest foe Hitler faced. Since the Catholic church believes that Hitler was influenced by Satan, Bonhoeffer would qualify as a saint. Whether or not he had the usual test of three miracles to back it up, is up to the Catholic church; in some cases, they are allowed to beatify an individual, without the requirements being entirely met. >>
I'm not sure that the above information is accurate. The "Confessing Church" was Protestant and did not include "Catholic denominations" and with all respect to Bonhoeffer I doubt if many people regard him as "he was the greatest foe Hitler faced2.
Bonheoffer has not in any formal sense been made a saint.
There's no single book, no 'key text'. "Mein Kampf", for example, contains a lot of autobiographical stuff by Hitler, much of it unreliable and dishonest. There's nothing comparable to Marx's "Kapital" or the major theoretical socialist works.
There were many influences - extreme nationalism, combined with race theories and eugenics. Many of the ideas were directed towards a specifically German "national renewal", and were treated with all the fervour of a substitute religion.
Some of the influences were very strange, including a belief in the occult.
Increasingly, the rather unsystematic ideology of Nazism became simply "the sayings of Adolf Hitler".
See the Related Link for "Wikipedia: Nazism" to the right. That article is something of a battleground. Please also look at the discussion page of the article.
"The foundation of the nineteenth century" by Houston Stewart Chamberlain + the work of Francis Galton.
Later the work of Alfred Rosenberg.
That would be Hermann Goering (Or Goring). He took a cyanide pill in his jail cell hours before his hanging.