Plutarch connects the sixth of the month Mounukhion to Apollon and Theseus--most importantly to Theseus' quest for the Minotaur--in his 'Life of Theseus'. Theseus vows to look over those the lots choose to be offered to the Minotaur in the maze on Krete. Plutarch continues:
"When the lot was cast, Theseus took those upon whom it fell from the Prytaneium and went to the Delphinium, where he dedicated to Apollo in their behalf his supplicant's badge. This was a bough from the sacred olive-tree, wreathed with white wool. Having made his vows and prayers, he went down to the sea on the sixth day of the month Munychion, on which day even now the Athenians still send their maidens to the Delphinium to propitiate the god." (XVIII)
The Delphinion was a shared temple, sacred to both Artemis Delphinia, and Apollon Delphinios. The title is confusing as it can relate to both the slaying of the dragon Delphyne--called 'Python' in the Homeric Hymn to Apollon--who guarded the oracle at Pytho, and to Apollon showing the Kretan colonists the way to Delphi, while riding on a dolphin or metamorphosing Himself into a dolphin. The latter is attested to in the Homeric Hymn to Apollon:
"I am the son of Zeus; Apollo is my name: but you I brought here over the wide gulf of the sea, meaning you no hurt; nay, here you shall keep my rich temple that is greatly honoured among men, and you shall know the plans of the deathless gods, and by their will you shall be honoured continually for all time. [...] Take out your goods and the gear of the straight ship, and make an altar upon the beach of the sea: light fire upon it and make an offering of white meal. Next, stand side by side around the altar and pray: and in as much as at the first on the hazy sea I sprang upon the swift ship in the form of a dolphin, pray to me as Apollo Delphinius; also the altar itself shall be called Delphinius and overlooking for ever." (474)
Artemis' title seems to be inherited through Her brother.
To understand Theseus' influence on this festival, I must first share more about him. As conflated from my posts on the mythical kings of Athens, and the Pyanepsia festival: Theseus had claimed his role as hero throughout Hellas, when he heard about the Minotaur of Krete, and the nine-yearly sacrifices to it. These sacrifices were a punishment by King Minos of Crete for the death of his son Androgeus, at the hands of Athenian assassins.
Theseus offered to be one of the youths who sailed for Krete. Once there, Ariadne, daughter of the king, fell for him and offered him a ball of yarn so he would be able to find his way out off the labyrinth that housed the Minotaur the youths would be sacrificed to. With Ariadne's aid, Theseus defeated the Minotaur, and brought the sacrificial children home. Theseus' return became the festival of Pyanepsia, celebrated on the seventh day of the month Pyanepsion (roughly around September).
Roughly in the month of Mounichion, the seafaring season started. It's therefor not odd that lots would have been cast about this time, for the youths--and everyone else with business across the sea--would set sail as soon as the weather allowed. The rising of the Pleiades, located in the constellation of Taurus, around late April, the beginning of May, was a signal for the boldest of sea-goers that the treacherous sea was at least moderately accessible. Still, it would be at least several months before the favored seafaring season started, so anyone braving the sea, could probably use some protection. Somewhere shortly after the Delphinia would have been Theseus' first opportunity to sail to Krete, but it would place his return almost five months later; quite some time for a three day journey (one way) in favorable conditions.
During the Delphinia, young maidens presented Apollon Delphinion, and perhaps Artemis Delphinia, with the iketiria Theseus had presented them with as well, in the hopes of receiving for the Athenians the same guidance and protection at sea as the Kretan colonists, as well as Theseus and the youths, had gotten.
Alternatively--or perhaps additionally--Robert Parker says in his 'Polytheism and Society at Athens', this event marked the start of an initiation period for girls and boys, the latter of which would make similar sacrifices at the Pyanepsia five months later. In Parker's own words:
"...Mounichion and Pyanopsion thus emerge, on evidence of the festivals celebrated during them, as ultimately associated with the young; and in myth Theseus and his companions are said to have set out during one, returned during the other. The hypothesis arises that the myth provides a model for the actual practices by which the young of Athens had once been brought to maturity: in Mounichion, still children, they left society, like the twice seven, for a period of seclusion, to return in Pyanopsion as adults. The myth in short reflects the ritual cycle by which - the difficult concept can no longer be avoided - the young were initiated."
Personally, I have found no corroborating evidence of this practice, but it does sound plausible that the time between the Delphinia and the Pyanepsia was a transitional time for boys and girls. I'm hesitant to accept Parker's entire explanation, however, without further evidence and research. I might visit this subject again in the future. It is interesting to note, that it can be inferred that both Artemis Delphinia and Apollon Delphinios are associated with protecting and guiding maidens and youths to womanhood and manhood.
A connection can also be made with Theseus visiting the shrine of Apollon Delphinios as an opportunity for purification before his great quest, as the young supplicants who prepared for their personal collective journeys into adulthood would desire purification of their own, and Apollon in many of his epithets is a purifier. Also, in a little less than a month, the Thargelia took place in Delos, an event where the births of Artemis, and especially Apollon were celebrated. The rites at the Delphinia might have been part of the purification processes for those who were to go to Delos (with thanks to Daphne Lykeia for this interpretation).
One fact that muddles the theories is that according to most translations of Plutarch's statement, the Delphinia takes place on the sixth, not the seventh, which makes a case for the worship of Artemis, not Apollon. Also, because it were maidens who gave the sacrifice, it seems more likely that Artemis was the one receiving supplication and not Her brother. Many scholars, including Jon D. Mikalson and Ernst Pfuhl, on whom Mikalson bases his opinion, support this notion. Plutarch's account, however, seems to counter this. It is a possibility, though, that maidens prayed to Artemis Delphinia at the Delphinia in the same way boys prayed to Apollon Delphinios at the Pyanepsia, and both for the same reasons.
What the purpose of the Delphinia actually was will remain a mystery for quite some time yet--perhaps it will always remain a mystery. We have theories, and a little bit of practice, based upon one source liable to translation and interpretation. Depending on your interpretation of the festival, and upon which aspect you want to focus most, there is a variety of ways one can celebrate the Delphinia.
For those of us who live nowhere near the sea, and who haven't set foot on a boat in years, the Delphinia might seem of little importance as a naval festival, but it is still a day that is sacred to Artemis--whether in her Delphinia persona or not--and Apollon Delphinios and Theseus as well. One can celebrate this day by offering Them both (to be sure) hymns, libations, and Popana cakes, and presenting Them with an iketiria, an olive branch wrapped with white wool--a form of the eiresione, used in rites of supplication, instead of celebration, decorated with white wool and ribbons only, not the first fruits and decorations of the eiresione above--while asking for the protection of all ships and sailors braving the water to bring you a large amount of the food found in your grocery store, the fish you eat, and a large part of the non-priority mail you receive. If you are a sailor yourself, or live and work on or with the water in any other way, you can make prayers for yourself and your colleagues/neighbors, for protection while presenting the Gods with the same (olive) branch.
In line with Parker, the Delphinia reigns in a transitional time, especially for young boys and girls. Similar to the youths Theseus took took Krete, and brought home, those in the right age bracket have the time from the Delphinia to the Pyanepsia to experience a more adult lifestyle. The youths were faced with the fear of the Minotaur, where young boys and girls today will most likely encounter something more along the lines of 'the summer of '69', but that's besides the point. If you are in the target age bracket, you can ask for guidance and blessings as you grow from boy/girl to man/woman (or any variation thereof), or alternatively, if you have a son or daughter transitioning, you can ask these blessings for them.
As a festival of purification, the Delphinia can be interpreted to be open to all who are going through a time of transition and/or struggle. A divine purification of miasma might allow you to focus better on these issues, and receive guidance from the Theoi more easily--like Theseus, who purified himself at the Delphinion and prayed for the guidance of Aphrodite directly thereafter. Aphrodite made Ariadne fall for him, saving his life and those of the young men and women in the process.
Image source: clipart.