We first a crown of low-growing lotus
having woven will place it on a shady plane-tree.
First from a silver oil-flask soft oil
drawing we will let it drip beneath the shady plane-tree.
Letters will be carved in the bark, so that someone passing by
may read in Doric: "Reverence me. I am Helen's tree."
Theocritus' epithalamium commemorating the ...
The story of Heracles being swallowed by the sea-monster appears in the Alexandra or Cassandra attributed to Lycophron:
αἰαῖ, τάλαινα θηλαμών, κεκαυμένη 
καὶ πρόσθε μὲν πεύκαισιν οὐλαμηφόροις
τριεσπέρου λέοντος, ὅν ποτε γνάθοις
Τρίτωνος ἠμάλαψε κάρχαρος κύων:
ἔμπνους δὲ δαιτρὸς ἡπάτων φλοιδούμενος 
τινθῷ λέβητος ἀφλόγοις ἐπ᾽ ἐσχάραις
Roman satirist Lucian of Somosata wrote of philosophers whose souls escaped from the Underworld. Names such as Plato, Socrates, even the founders of Stoicism which was popular in the second-century Roman Empire. They were angry with Lucian, who had placed himself as a character in this particular story. He had, in their eyes, insulted them and Philosophy ...
Plato’s Republic includes the myth of Er, son of Armenius, in which Er avoids drinking the water of Lethe and so escapes from the underworld:
All the souls […] marched on in a scorching heat to the plain of Forgetfulness [Lethe], which was a barren waste destitute of trees and verdure; and then towards evening they encamped by the river of Unmindfulness [...
I doubt that this has anything to do with Mediterranean cultures specifically.
The myth of Izanagi/Izanami in Japanese Shinto is straightforwardly identical to the myth of Orpheus (only that the protagonists are gods in the Japanese myth).
Also Greek myths and other myths in the region could have been influenced by other previous non-Mediterranean cultures. ...
Herodotus, in his Histories, recounts the story of how Ariston took his third wife, the most beautiful woman in Sparta, from his friend Agetus, and says that she had been an ugly baby, but her nurse's constant prayers at Helen's shrine had caused Helen to appear and make her beautiful.
If the story is not accurate, nevertheless the existence of the shrine is ...