A son of Porthaon, king of Calydon in Aetolia, and Euryte; he was the brother of Oeneus (who succeeded his father as king of Calydon), Alcathous, Melas, Leucopeus, and Sterope. He was father of six sons, including Melanippus and Thersites, who overthrew Oeneus and gave the kingdom to their father. Agrius and his sons were themselves overthrown by Diomedes, who reinstated Oeneus as king. All the sons except Thersites were killed by Diomedes. The Bibliotheca places these events before the expedition of the Greeks against Troy, while Hyginus states that Diomedes, when he heard, after the fall of Troy, of the misfortune of his grandfather Oeneus, hastened back and expelled Agrius, who then committed suicide; according to others, Agrius and his sons were all slain by Diomedes.
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