Immortals (Achaemenid Empire)
Immortals (Greek: Ἀθάνατοι, Athánatoi), or Persian Immortals, was the name given by the Greek historian Herodotus to a 10,000-strong unit of elite heavy infantry in the Achaemenid army. They served in a dual capacity, operating as an imperial guard and contributing to the ranks of the standing army.
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