Note: Also transliterated as “Dadaphoria”. Lit. “Torch processions”
The Daidaphoria ("bearing of torches") was a festival likely celebrated in honour of Dionysos. It coincided with the start of his winter rule to Delphi and may have marked his return, his rebirth, or his ritual death at the hands of the Thyiads. The festival was known to be “trieteric”, celebrated on the third year, and may have differed in the year the Thyiads were absent.
Dadaphoria is linked to Dionysos' "torch bearer" epithet, with Euripides describing him as “bounding with his torches among the crags at Delphi”. Though its rituals are unknown, it is likely connected to the celebrations of the Thyiads known to have included feasting, dancing, and torchlight processions on Mt Parnassos.
They give him the names of Dionysus, Zagreus, Nyctelius, and Isodaetes; they construct death and disappearance, followed by revival and rebirth
– Plutarch, On the E at Delphi
"Every two years, the birth of Dionysos – every two years, the death of Dionysos";
– Pomtow, "Delphoi," col. 1532.
It was held in the fifth month, Daidaphorios, but likely celebrated differently every other year. The torchlight rite, from which this festival gets its name, are termed trieteric - happening on every third year.
A two-year period called a trieteris ("three years") was common to Dionysian worship in the Northern parts of Greece. The first year he is thought to reside below ground, the second above. Dionysos was given two names during this period. He was called "Trieterikos" in relation to his festivals which occurred in the third year and "Amphietes" meaning "he of both years".
In order for the trieteris to begin, Dionysos was absent for twelve months. According to Hymn to Amphietes, he spent this period in the holy palace of Persephone and was worshipped as Chthonios "subterranean".
At the end of the two years, Dionysos closed one period and began a new one, with the help of the nymphs who awakened the god and reawakened the trieteric period.
άναβόασον αύτώι Διόνυσον άείσομεν Ιεpαίς έν ήμέpαις δώδεκα μήνας άπόντα πάpα δ’ ώpα, πάpα δ' άνθη'
Cry out to him: We shall sing Dionysos On the holy days, Him who was twelve months absent. Now the time has come, now the flowers are here.
– Rainer papyrus (1st c. b.c. or 1st c. a.d.)
On the 13th of the month, the moon intersects with the bull Made with Stellarium $^{71}$ and google maps
It took place in the fifth month, and some have suggested it might be connected to Artemis or Hekate due to their very well known epithets Daidouchos and Phosphoros, however Dionysos also bears the title "torch bearer" and his worship in Delphi is strongly connected to torches in literary sources. Euripides describes him as seen "bounding with torches among the crags at Delphi", and he is called “torch-god” by Lykophron*.*
Some day you shall even see him bounding with his torches among the crags at Delphi, leaping the pastures that stretch between the peaks, whirling and waving his thyrsus : great throughout Hellas
– Euripides, Bacchae, 306-309, trans. by W. Arrowsmith.
To Bacchos, as their rescuer from their previous trouble, they will cry Euai! and call him the Tripper-up. To him, in the recesses of Delphinios, by the cave of the Cunning One, the fleet-commander of a thousand city-sacking ships will begin the secret sacrifice to the Bull-god.
To him, in unexpected requital for his sacrifices, the Potent one, the Phigaleian, the Torch-god entwines the lion’s feet in tendrils, and keeps him away from his feast, so that he cannot utterly lay waste the corn by ravaging it with his teeth and voracious jaws.
– The Alexandra of Lykophron
and he who haunts Parnassus’ rock and glows in the light of pine torches, eminent among Delphic bacchants, the reveller Dionysus.
– Aristophanes, Clouds, 603-607