According to the Encyclopedia Britannica, an invasion theory about the "Aryan race" emerged in the middle of the 19th century in Europe. This theory hypothesized that Aryans came from the north and conquered Iran and northern India during prehistory.
Later, Adolf Hitler and the Nazis created a mythology around the hypothesized race, basing the murders of millions of Jewish and Roma people on the perceived superiority of the Aryans. The Encyclopedia Britannica clarifies, however, that the term "Aryan" is no longer used by most scholars to describe a racial group. The term continues to be used in linguistics, referring to the Indo-Aryan branch of the Indo-European family of languages.