Immortals (Achaemenid Empire)

Immortals (Ancient Greek: Ἀθάνατοι, romanized: Athánatoi) or Persian Immortals was the name given by Herodotus to an elite heavy infantry unit of 10,000 soldiers in the army of the Achaemenid Empire. The unit served in a dual capacity through its role as imperial guard alongside its contribution to the ranks of the Persian Empire's standing army. While it primarily consisted of Persians, the Immortals force also included Medes and Elamites. Essential questions regarding the historic unit remain unanswered because authoritative sources are missing.^[2]