What was the name of the Greek seer who advised the Achaeans? The answer is Calchas. In the Iliad and related Trojan War traditions, Calchas was the Achaean army’s prophetic interpreter, trusted to explain the will of the gods and identify the religious causes of disaster.
At the beginning of the Iliad, Apollo sends a plague through the Greek camp after Agamemnon dishonors Chryses, Apollo’s priest. Calchas explains that the plague will continue until Chryseis is returned to her father and proper sacrifices are made. His revelation forces Agamemnon to give up the captive woman, though Agamemnon then takes Briseis from Achilles, beginning the poem’s central quarrel.
Calchas is not the same figure as Tiresias, the famous Theban prophet associated especially with Oedipus and the Odyssey. Nestor was an elderly king and counselor, while Phoenix was Achilles’ tutor and companion. Calchas’ authority came specifically from prophecy and his interpretation of divine signs.