The Aryan race was a racial grouping term used in the period of the late 19th century to the mid-20th century to describe multiple peoples. It has been variously used to describe all Indo-Europeans in general (spanning from India to Europe), the original Aryan people specifically in Persia, and most controversially through Nazi misinterpretation, the Nordic or Germanic peoples. The term derives from the Aryan people, from Persia, who spoke a language similar to those that have been found in Europe.
While originally meant simply as a neutral ethno-linguistic classification, from the late 19th century onwards the term Aryan race has been used by people who promoted ideas about racial hierarchy, like the Nazis, who thought that the Germanic peoples were, in comparison to other peoples in the world, predominately descended from an ancient master race, whom they called "Aryan".Aryanism developed as a racial ideology based on this idea.
The term Aryan originates from the Sanskrit word ārya (Devanāgarī: आर्य), in origin an ethnic self-designation, in Classical Sanskrit meaning "honourable, respectable, noble".
In the 18th century, the most ancient known Indo-European languages were those of the ancient Indo-Iranians. The word Aryan was therefore adopted to refer not only to the Indo-Iranian peoples, but also to native Indo-European speakers as a whole, including the Romans, Greeks, and the Germans. It was soon recognised that Balts, Celts, and Slavs also belonged to the same group. It was argued that all of these languages originated from a common root—now known as Proto-Indo-European—spoken by an ancient people who were thought of as ancestors of the European, Iranian, and Indo-Aryan peoples. The ethnic group composed of the Proto-Indo-Europeans and their modern descendants was termed the "Aryans".