Medes were an ancient Iranian people, they spoke Median and lived in Media, which was northwest Iran. A great portion of their history is missing as there was no written source left. The most that is understood about them comes from foreign sources such as the Assyrians, Babylonians, Armenians, and Greeks. It is suggested that the Median empire was a very strong kingdom that competed with Babylonia. The Medes founded the first Iranian nation in the seventh century B.C, but it ended up being destroyed by Cyrus the Great, who then went on to establish the Persian empire. Persia is the Greek name. Iranians are descendants of the Medes and the Persians.
Thanks for the definition.
-Prof. Scanlan