Overview
The eagle is used in heraldry as a charge, as a supporter, and as a crest. Heraldic eagles can be found throughout world history like in the Achaemenid Empire or in the present Republic of Indonesia. The European post-classical symbolism of the heraldic eagle is connected with the Roman Empire on one hand (especially in the case of the double-headed eagle), and with Saint John the Evangelist on the other.
History
A golden eagle was often used on the banner of the Achaemenid Empire of Persia. Eagle (or the related royal bird vareghna) symbolized khvarenah (the God-given glory), and the Achaemenid family was associated with eagle (according to legend, Achaemenes was raised by an eagle). The local rulers of Persis in the Seleucid and Parthian eras (3rd-2nd centuries BC) sometimes used an eagle as the finial of their banner. Parthians and Armenians used eagle banners, too.
European heraldry
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