Not just Hitler, the whole of the Nazi party and their public propaganda was based on extreme Darwinism.

An important official Nazi Party publication, Nationalsozialistische Monatshefte, edited by Alfred Rosenberg, occasionally featured articles promoting evolution. In a 1935 article Heinz Brücher praised German biologist Ernst Haeckel for paving the way for the Nazi regime. In addition to mentioning Haeckel's advocacy of eugenics and euthanasia, Brücher highlighted Haeckel's role in promoting human evolution. Brücher reminded his readers that Haeckel's view of human evolution led him to reject human equality and socialism. In 1941 Brücher published another article in Nationalsozialistische Monatshefte on evolution through natural selection. Several times he stressed that the principles of evolution were just as valid for humans as for other orgarisms. He closed the essay by explaining the practical application of evolutionary theory:

The hereditary health of the German Volk and of the Nordic-Germanic race that unites it must under all circumstances remain intact. Through an appropriate complianmce with the laws of nature, through selection and planned racial care it can even be increased. The racial superiority achieved thereby secures for our Volk in the harsh struggle for existence an advantage, which will make us unconquerable.

In Brücher's view human evolution is an essential ingredient of racial ideology, not a hindrance to it. In 1936 Heberer launched an attack on antievolutionists in Nationalsozialistische Monatshefte. He praised Haeckel and stressed the affinities of Darwinism and human evolution with Nazi ideology.

The history is really quite fascinating and it's rarely taught in your state-mandated evolutionary biology classes!