Houston Stewart Chamberlain
Houston Stewart Chamberlain (1855-1927) was born in Britain, but became fascinated with German culture and eventually became a German citizen, producing most of his work in that language. While he had a wide range of interests, including literature, biology, politics, religion and music, he is most known as the key inspiration of the mixture of race and history, which became the Nazi race and biological ideology. He and Adolf Hitler were mutually impressed with one another, although they met in person only shortly before Chamberlain's death.
He was a significant influence on the thinking of Hitler. Even to Hitler's anti-Nazi biographer, Konrad Heiden, who vehemently disagreed with Chamberlain's racism, "he was one of the most astonishing talents in the history of the German mind, a mine of knowledge and profound ideas." Perhaps his most important book was Foundations of the Nineteenth Century (Grundlagen des Neinzehnten Jahrhunderts), published in 1899, and praised by Kaiser Wilhelm II. Its title is ironic when compared to another Nazi inspiration, Alfred Rosenberg's Myth of the Twentieth Century, often considered incomprehensible and incoherent.
Certain anthropologists would fain teach us that all races are equally gifted; we point to history and answer: that is a lie! The races of mankind are markedly different in the nature and also in the extent of their gifts, and the Germanic races belong to the most highly gifted group, the group usually termed Aryan. Is this human family united and uniform by bonds of blood? Do these stems really all spring from the same root? I do not know and I do not much care...
He considered the Teutons and the Jews the only true races, including the Slavs and Celts in the Teutons. Condemning "stupid and revolting anti-semitism", he observed that the Jews were not inferior to the Teuton, only different. He suggested they have their own grandeur and their need to protect their race. Nevertheless, he drifted into antisemitism that reappeared, as caricatures, in the writing of Julius Streicher.
At the age of 19, he met and married Anna Horst, a Prussian, in 1874. Meeting Richard Wagner in 1882, he found him the "sun of his life", and idolized Cosima Wagner, the composer's wife, as well. Eventually, he would divorce Anna in 1905, and three years later marry Eva, Wagner's daughter, so he could live near Cosima. 
Chamberlain and Hitler met in 1923, at a Wagnerian festival. Chamberlain wrote an 1924 article praising Hitler, who was imprisoned at the time. Hitler was the only public figure, other than a prince representing the Kaiser, to be at Chamberlain's funeral. 
- William Shirer (1960), The Rise and Fall of the Third Reich, Simon & Schuster, pp. 105-106
- Foundations of the Nineteenth Century, Volume I, p. 542, quoted by 
- Shirer, p. 105
- Timothy W. Ryback (2009), Hitler's Private Library: The Books That Shaped His Life, Random House, p. 69
- Shirer, p. 109