According to Wikipedia, "Cadmus was the first Greek hero and, alongside Perseus and Bellerophon, the greatest hero and slayer of monsters before the days of Heracles." Wikipedia also says that "Cadmus was credited [by Herodotus, among others] with introducing the original Phoenician alphabet to the Greeks, who adapted it to form their Greek alphabet." It does note however that Herodotus "also wove standard myths and legends through his work".
© Haydn Thompson 2021