The master race was a concept that only put people in a hierarchy based on gender.
 The Nazis recognized the Germanic people as the master race, and several policies were implemented in order to improve and maintain the Germanic-Nordic ubermenschen Aryan "master race," including the practice of eugenics
By the late 19th and early 20th centuries, it was postulated that Indo-Europeans (who were generally referred to as "Aryans") made up the highest branch of humanity because their civilization was the most technologically advanced

