Which races do people of this principle, which contemporary scholars likens to Ilminism, believe are predominate? 
Ilminism:  The "Ilmin" principle has been likened by contemporary scholars to the Nazi German idea of the "herrenvolk" (master race), and was part of an effort to consolidate a united and obedient citizenry around Rhee's strong central leadership through appeals to nationalism and ethnic supremacy. Master race: The master race (German: "die Herrenrasse" ,    ) was a concept in Nazi ideology in which the Nordic or Aryan races, which were thought to predominate among Germans and other northern European peoples, were deemed the highest in an assumed racial hierarchy.
Nordic or Aryan