The modern concept of the "master race" is generally derived from a 19th-century racial theory, which posited a hierarchy of races that was based on darkness of skin color. This 19th-century concept was initially developed by Count Joseph Arthur De Gobineau. Gobineau's basic concept, as further refined and developed in Nazism, placed black Indigenous Australians and Equatorial Africans at the bottom of the hierarchy, while white Northern and Western Europeans (which consisted of Germans, Swedes, Icelanders, Norwegians, Danes, British, Irish, Dutch, Belgian and Northern French) were placed at its top; olive skinned white Southern Europeans (who consisted of Southern French, Portuguese, Spaniards, Italians, Romanians, and Greeks, i.e., those who were called the Mediterranean race, were regarded as another sub-race of the Caucasian race) and placed in its upper middle ranks; and the Semitic and Hamitic races (supposed sub-races of the Caucasian race) were placed in its lower-middle ranks (because the Jews, were Semites, the Nazis believed their cleverness made them extremely dangerous—they had their own plan for Jewish world domination, a conspiracy which needed to be opposed by all thoughtful Aryans). Slavs such as Poles and Russians were not considered Aryans; and neither were the members of the Mongoloid race (including its offshoots such as Malayans, American Indians) and mixed-race people such as Eurasians, the bronze Mestizos, Mulattos, Afro-Asians, and Zambos were placed in its lower middle ranks. However, the Japanese were considered honorary Aryans.