The ancient nation of Iran was historically known to the West as Persia until March 21, 1935 (see also History of Persia, History of Levant). Once a major empire in its own right, Iran has been overrun frequently and has had its territory altered throughout the centuries. Invaded by Arabs, Seljuk Turks, Mongols, and others--and often caught up in the affairs of larger powers--Iran has always reasserted its national identity and has developed as a distinct political and cultural entity.