 In fact, when Thersites was brutally slain by Achilles (after having mocked him when the latter cried over Penthesilia's dead body), Diomedes was the only person who wanted to punish Achilles.Diomedes became one of the suitors of Helen and, as such, he was bound by the oath of Tyndareus, which established that all the suitors would defend and protect the man who was chosen as Helen's husband against any wrong done against him in regard to his marriage.Accordingly, when the Trojan prince Paris stole Menelaus' wife, all those who had sworn the oath were summoned by Agamemnon (Menelaus’ brother), so that they would join the coalition that was to sail from Aulis to Troy in order to retrieve Helen and the Spartan property that was stolen.