The book of Esther calls them that as the people from Fars were the elite of the Achaemenid empire. But they called themselves Aryans. Just as the Vedic North Indians called themselves Aryans
Nothing whatsoever to do with the Germans.
Fars is after the Euphrates River, Nhar Pras in Hebrew.
Wherever this whole “Aryan” notion comes from, it’s not Germanic or Nordic peoples, and it has nothing to do with the myth about the sunken city of Atlantis, either.