Melampus[1]
A legendary soothsayer and healer, originally of Pylos, who ruled at Argos. He introduced the worship of Dionysus, according to Herodotus, who asserted that his powers as a seer were derived from the Egyptians[2] and that he could understand the language of animals. A number of pseudepigraphal works of divination were circulated in Classical and Hellenistic times under the name Melampus. According to Herodotus and Pausanias (vi.17.6), on the authority of Hesiod, his father was Amythaon, whose name implies the "ineffable" or "unspeakably great";[3] thus Melampus and his heirs were Amythaides of the "House of Amythaon".Again, there isn't much of a factual nature about Orpheus though there is a lot of speculation about Orphism. So, Wikipedia again:
In Homer's Odyssey,[4] a digression concerning the lineage of Theoclymenus, "a prophet, sprung from Melampus' line of seers",[5] sketches the epic narrative concerning Melampus with such brevity that its details must have been familiar to Homer's audience. With brief hints, a sequence of episodes is alluded to, in which we discern strife in Pylos between Melampus and Neleus, who usurps Melampus's "great high house", forcing him into heroic exile. Melampus spends a year as bondsman in the house of Phylacus, "all for Neleus' daughter Pero". At his extremity, Melampus is visited by "the mad spell a Fury, murderous spirit, cast upon his mind. But the seer worked free of death" and succeeded at last in rustling Phylacus's cattle back to Pylos, where he avenged himself on Neleus and gave Pero in marriage to his brother Bias. But Melampus's own destiny lay in Argos, where he lived and ruled, married and sired a long line, also briefly sketched in Homer's excursus.
A work attributed in antiquity to Hesiod exists (Melampodia) in such fragmentary quotations and chance remarks that its reconstruction, according to Walter Burkert,[6] is "most uncertain." (Wikipedia)
Comment: Other ancient settlements across Europe, that were situated on similarly wet terrain, even on the bodies of water themselves, seem to point to there being extremely wet periods, in addition to other clues showing defensive measures were of importance, perhaps due to societal unrest: