|According to Mein Kampf (My Struggle), Hitler developed his political theories after carefully observing the policies of the Austro-Hungarian Empire. He was born as a citizen of the Empire, and believed that ethnic and linguistic diversity had weakened it. Further, he saw democracy as a destabilizing force, because it placed power in the hands of ethnic minorities, who he claimed had incentives to further "weaken and destabilize" the Empire.
The Nazi rationale was heavily invested in the militarist belief that great nations grow from military power, which in turn grows "naturally" from "rational, civilized cultures." Hitler's calls appealed to disgruntled German Nationalists, eager to save face for the failure of World War I, and to salvage the militaristic nationalist mindset of that previous era. After Austria and Germany's defeat of World War I, many Germans still had heartfelt ties to the goal of creating a greater Germany, and thought that the use of military force to achieve it was necessary.
Many placed the blame for Germany's misfortunes on those whom they perceived, in one way or another, to have sabotaged the goal of national victory. Jews and communists became the ideal scapegoats for Germans deeply invested in a German Nationalist ideology.
Hitler's Nazi theory also claimed that the Aryan race is a master race, superior to all other races, that a nation is the highest creation of a race, and great nations (literally large nations) were the creation of great races. These nations developed cultures that naturally grew from races with "natural good health, and aggressive, intelligent, courageous traits." The weakest nations, Hitler said were those of impure or mongrel races, because they have divided, quarrelling, and therefore weak cultures. Worst of all were seen to be the parasitic Untermensch (Subhumans), mainly Jews, but also Gypsies, homosexuals, disabled and so called anti-socials, all of whom were considered lebensunwertes Leben (Lifeunworthy Life) due to their perceived deficiency and inferiority. The role of homosexuals during the Holocaust are controversial among historians. Some, like the International Committee for Holocaust Truth and authors Scott Lively and Kevin E. Abrams in "The Pink Swastika: Homosexuality in the Nazi Party", defend the perspective that many homosexuals were involved in the inner circle of the Nazi party: Ernst Röhm of the SA, Horst Wessel, Max Bielas, and others. This perspective is denounced as hateful propaganda by most homosexual associations and groups, stirring heated debates and accusations of censorship and "hate-speech" from both sides.
People of the Eastern European Russian-dominated Slavic descent were also seen as subhuman, but only marginally parasitic, because they had their own land and nations, though many of them lived in German countries such as Austria, which Hitler saw as an ethnic invasion of Germanic Lebensraum by foreign populations who would have incentive to force Austria's loyalty to their lands of ethnic and cultural origin.
According to Nazism, it is an obvious mistake to permit or encourage multilingualism and multiculturalism within a nation. Fundamental to the Nazi goal was the unification of all German-speaking peoples, "unjustly" divided into different Nation States. Hitler claimed that nations that could not defend their territory did not deserve it. Slave races, he thought of as less-worthy to exist than "master races." In particular, if a master race should require room to live (Lebensraum), he thought such a race should have the right to displace the inferior indigenous races. Hitler draws parallels between Lebensraum and the American ethnic cleansing and relocation policies towards the Native Americans, which he saw as key to the success of the US.
"Races without homelands," Hitler claimed, were "parasitic races," and the richer the members of a "parasitic race" are, the more "virulent" the parasitism was thought to be. A "master race" could therefore, according to the Nazi doctrine, easily strengthen itself by eliminating "parasitic races" from its homeland. This was the given rationalization for the Nazi's later oppression and elimination of Jews and Gypsies. Despite the popularity of Hitler and his living space doctrine, some Wehrmacht and Waffen-SS soldiers found the duty repugnant. Only a small fraction of them were actively involved in genocide.
Hitler extended his rationalizations into religious doctrine, claiming that those who agreed with and taught his "truths," were "true" or "master" religions, because they would "create mastery" by avoiding comforting lies. Those that preach love and tolerance, "in contravention to the facts," were said to be "slave" or "false" religions. The man who recognizes these "truths," Hitler continued, was said to be a "natural leader," and those who deny it were said to be "natural slaves." "Slaves," especially intelligent ones, he claimed were always attempting to hinder masters by promoting false religious and political doctrines.
The ideological roots which became German "National Socialism" were based on numerous sources in European history, drawing especially from Romantic 19th Century idealism, and from a biological misreading of Friedrich Nietzsche's thoughts on "breeding upwards" toward the goal of an Übermensch (Superhuman). Hitler was an avid reader and received ideas that were later to influence Nazism from traceable publications, such as those of the Germanenorden (Germanic Order) or the Thule society.