Dionysos had absorbed into his personality two non-Hellenic divinities--(1) a god of wine, orgy, and ecstasy from Thrace, (2) a Cretan mystery god, Zagreus, who is substantially one with the Egyptian god of immortality, Osiris.
As to his origin, though his name means, undoubtedly, "young Zeus," Dionysos is essentially the son of his mother, Semele; later he is affiliated to Zeus by a rebirth.
The Bacchantes are the mothers; they tend the young of wild things, and they have magical power to make the whole world break into blossom.
At the great ritual of the mothers all Creation stirs anew.
No wonder Dionysos and his mother did not find easy access to a patriarchal Olympus!
The worship of Dionysos has one characteristic that distinguishes him from the other gods, and is of special interest in helping us to understand the making of a god. Dionysos is always accompanied by a worshipping band, a thiasos. His worshipping band are the Satyrs, his mother's are the Mænads. None of the other gods have a thiasos. The reason is clear, once the psychology
By becoming one with the god he had projected, the worshipper of Dionysos attained immortality. That is the doctrine of each and every mystery religion. No one sought to become Zeus or Athene or Apollo. That would have seemed folly and insolence. "Strive not thou to become a god," says Pindar; "the things of mortals best become mortality."
It is probable that all Greek gods were originally accompanied by a thiasos, and were projected by their worshippers. But most of the Olympians have long passed this stage. Their worship is not an ecstasy; it is a sober service of sacrifice, prayer, and praise. God and man are eternally sundered.
Another trait marks Dionysos off from the Olympians. They are wholly human; he keeps about him some vestiges of plant and animal shape. He is tree-god (dendrîtes), and at will he can change himself back into plant or animal form. When the Bacchantes in extreme peril call upon Dionysos for vengeance, his ancient incarnations loom in upon their maddened minds: