The master race (Herrenrasse) is a pseudoscientific concept in Nazi ideology in which the putative "Aryan race" is deemed the pinnacle of human racial hierarchy. Members were referred to as "Herrenmenschen" ("master humans").
The Nazi theorist Alfred Rosenberg believed that the "Nordic race" was descended from Proto-Indo-Europeans, who he believed had pre-historically dwelt on the North German Plain and may have ultimately originated on the lost island of Atlantis. The Nazis declared that the Aryans were superior to all other races, and believed they were entitled to expand territorially. The actual policy that was implemented by the Nazis resulted in the Aryan certificate. This document, which was required by law for all citizens of the Reich, was the "Lesser Aryan certificate" (Kleiner Ariernachweis) and could be obtained through an Ahnenpass, which required the owner to trace their lineage through baptism, birth certificates, or certified proof thereof that all grandparents were of "Aryan descent".
The Slavs, Roma, and Jews were defined as being racially inferior and non-Aryan "Untermenschen", and were thus considered to be a danger to the Aryan or Germanic master race. According to the Nazi secret Hunger Plan and Generalplan Ost, the Slavic population was to be removed from Central Europe through expulsion, enslavement, starvation, and extermination, except for a small percentage who were deemed to be non-Slavic descendants of Germanic settlers, and thus suitable for Germanisation.
Early attempts to claim a racial division between "masters" and "slaves", or the belief that a nation's ruling class is biologically superior to its ruled subjects, were made in the 18th century. Henri de Boulainvilliers in his book History of the Ancient Government of France (published posthumously in 1727) tried to prove that in France, the nobility represented the descendants of the old Frankish ruling class, whereas the rest of the population was descended from the subject Gauls.