In the post-enlightenment Europe of the 19th century the highest authority was no longer the Church. Instead it was science. Thus was born racial anti-Semitism based on two disciplines regarded as science in their day - the 'scientific study of race' and the Social Darwinism of Herbert Spencer and Ernst Haeckel.
As a world view Darwinism cannot of course be refuted since Faith is always has been and always will be stronger than facts.