The festival of assembly
The Apellai festival was a festival of assembly held in honour of the god Apollon. It was an important landmark festival in the calendar of the Labyadai, who were a phratry or kinship group of Delphi. The festival likely marked the beginning of the year and the acceptance of youth into adult society. A sacrifice to Dionysus was also part of the festival. It was a gathering of the Labyadai, and was likely a way to mark the beginning of the year and the acceptance of youth into the adult society.
Either the 1st of the month, or the 7th. It is rare in the Attic calendar to celebrate festivals on the 1st, but it is unclear that the same rules applied elsewhere. This is the festival that marked the start of the new year, which makes the 1st a good choice. The 7th is the date given to Daidaphoria, however that only takes place every 9th year.
Furthermore, a special link was noticed between certain days of the month and the god Apollo, notably the day of the new moon and the seventh day, the latter being considered his birthday (cf. Hesiod, Works and Days 770-1; Herodotos 6.57; scholion to Aristophanes, Wealth 1126; Nilsson 1962: 38-9)
– Robert Hannah, Greek and Roman Calendars $^{8}$
Regrettably, the sources do not inform us much further about the rituals undertaken during this great gathering or on what date Apollo was honoured. The 7th day of Apellaios is a good possibility, given the predilection for rites in honour of the god on that day; see here lines D5-7 on 7 Bysios and cp. also 7 Hekatombaion in Athens, to which this date may roughly correspond: CGRN 56 (Marathonian Tetrapolis), col. I, lines 24-26. For a sacrifice to Dionysus also taking place during this festival, see below lines D43-51.
– A Collection of Greek Ritual Norms (CGRN) $^{5}$
The festival of Apellai in Apellaios is mentioned in this late 5th/early 4th-century inscription from Delphi, 1A31–2, 36, B7, D3 Rhodes and Osborne, but apparently the sacrifices were offered to Dionysus, 1D 44–5 Rhodes and Osborne (Rhodes and Osborne (2003) 2–7; Farnell (1907) 99 n. b notes that neither the festival nor the sacrifices are explicitly associated with Apollo). On the festival of Apellai at Delphi see especially Burkert (1975) 10, who interprets it as an initiation ceremony; it was not celebrated generally at Delphi, however (Rhodes and Osborne (2003) 11).
– Tomislav Bilić, Calendric Aspects of Myths and Cults Involving Apollo's Visit to Hyperborea $^{45}$
This phratria celebrated an annual festivity, apellai, in the month Apellaios, for which some special offerings and victims, in accordance with the rules here established, are required. The offerings are classified in three groups: [Greek omitted] (the latter undoubtly cattle, as may be deduced from the verb [Greek]),
– A Collection of Greek Ritual Norms (CGRN) $^{5}$
The Apellai festival was a celebration that took place in the month of Apellaios in honour of the god Apollon. The exact date of the festival is uncertain, but it may have been on the 1st or 7th day of the month. The Apellai festival was an important event in Delphic society, and it involved special offerings, including a sacrifice to Dionysus. The festival was one of the principal occasions for sacrifice and assembly in the group of the Labyadai. Despite the importance of the Apellai festival, our sources do not provide much information about this festival. However, it is clear that the festival involved special offerings, sacrifice, and assembly.
Burkert, following the interpretation of Homollél, has emphasised the relevance of this witness as a case for a Delphic 'Ephebenfest', close to the attic Apatouria (where we have a sequence of offerings)
The beginning of the year is marked out by the events that underline the renewal and the cohesion of the society, as well as by the timai for the main local gods, The Apellai mark the acceptance of youth in the adult society, and a thoina of the phratria is prescribed, But the other important Delphic god, Dionysos, is not forgotten: he is honored with a thysia
– Emilio Suárez de la Torre, Neoptolemos at Delphi $^{15}$
Apellaios is the first month of the calendar of Delphi and the Apellai, in honour of Apollo (cf. LSJ s.v. Ἀπέλλων for the Dorian form; cf. here CGRN 2, Gortyn, line 2), appropriately occur first here. As mentioned above in the discussion of faces A-C, the Apellai were clearly one of the principal occasions for sacrifice and assembly in the group of the Labyadai, and in fact sources gloss the verb ἀπελλάζω as a Spartan or Doric verb meaning "to hold an assembly" (see LSJ s.v.).
The ἀπελλαῖα mentioned on faces A-B (see above) must however clearly have been sacrificial animals as they are led (ἄγεν) for this specific occasion. Regrettably, the sources do not inform us much further about the rituals undertaken during this great gathering or on what date Apollo was honoured. The 7th day of Apellaios is a good possibility, given the predilection for rites in honour of the god on that day; see here lines D5-7 on 7 Bysios and cp. also 7 Hekatombaion in Athens, to which this date may roughly correspond: CGRN 56 (Marathonian Tetrapolis), col. I, lines 24-26. For a sacrifice to Dionysus also taking place during this festival, see below lines D43-51.
– A Collection of Greek Ritual Norms $^{5}$