Nordic theory (or Nordicism) was a theory of racial supremacy prevalent in the late 19th and early 20th century, which claimed that North European peoples constitute a “master race” because of their innate racial capacity for leadership. Nordic theory was influential in Western Europe and North America during the early 20th century and was a major influence on Nazi ideology.
The theory drew on the dominant anthropological model of racial categories prevalent in the early 20th century, according to which Europeans were divided into three main sub-categories of the Caucasian race: the Nordic, Alpine and Mediterranean races. The Nordic race was thought to be prevalent in northern Europe, especially, but not exclusively, among speakers of the Germanic languages, and was characterized by tall stature, wide shoulders, long head- and facial form, straight and fine blond, red, or light brown hair, and blue, grey or green eyes. The Alpine race was thought to predominate in central Europe, and was said to be characterized by short stature, dark hair, dark eyes, narrower shoulders and comparatively round head. The Mediterranean race was thought to be prevalent in southern Europe, Middle East and North Africa, and was said to be characterised by dark hair, dark eyes, narrower shoulders, swarthy complexion, moderate-to-short stature, and moderate of skull.
Adolf Hitler read Human Heredity shortly before he wrote Mein Kampf, and called it scientific proof of the racial basis of civilization. Its arguments were also repeated by the Nazi ideologist Alfred Rosenberg, in his book The Myth of the Twentieth Century (1930). Rosenberg argued that the Nordic race had evolved in a now-lost landmass off the coast of North Western Europe, and had migrated through Scandinavia and northern Europe, expanding further south, and as far as Iran and India where it founded the Aryan cultures of Zoroastrianism and Hinduism. Like Grant and others, he argued that the entrepreneurial energy of the Nordics had "degenerated" when they mixed with "inferior" peoples.
With the rise of Hitler, Nordic theory became the norm within German culture. In some cases the "Nordic" concept became an almost abstract ideal rather than a mere racial category. Hermann Gauch wrote in 1933 that the fact that "birds can be taught to talk better than other animals is explained by the fact that their mouths are Nordic in structure." He further claimed that in humans, "the shape of the Nordic gum allows a superior movement of the tongue, which is the reason why Nordic talking and singing are richer."
Such views were extreme, but more mainstream Nordic theory was institutionalized. Hans Günther, who joined the Nazi Party in 1932, was praised as a pioneer in racial thinking, a shining light of Nordic theory. Most official Nazi comments on the Nordic Race were based on Günther's works, and Alfred Rosenberg presented Günther with a medal for his work in anthropology. Fischer and Lenz were also appointed to senior positions overseeing the policy of Racial Hygiene. Madison Grant's book was the first non-German book to be translated and published by the Nazi Reich press, and Grant proudly displayed to his friends a letter from Hitler claiming that the book was "his Bible." The Nazi state used such ideas about the differences between European races as part of their various discriminatory and coercive policies which culminated in the Holocaust. Ironically, in Grant's first edition of his popular book, he classified the Germans as being primarily Nordic, but in his second edition, published after the USA had entered WWI, he had re-classified the now enemy power as being dominated by "inferior" Alpines. Günther's work agreed with Grant's, and the German anthropologist frequently stated that the Germans are definitely not a fully Nordic people. Hitler himself was later to downplay the importance of Nordicism for this very reason. The standard tripartite model placed most of the population of Hitler's Germany in the Alpine category, especially after the Anschluss. By 1939 Hitler abandoned Nordicist rhetoric in favour of the idea that the German people as a whole were united by distinct "spiritual" qualities. Nevertheless, Nazi eugenics policies continued to favor Nordics over Alpines and other German racial groups.