[1] Independent of the division of a month into days, it was divided into periods according to the increase and decrease of the moon.
Each of the city-states in ancient Greece had their own calendar that was based on the cycle of the moon, but also the various religious festivals that occurred throughout the year.
It was not until the second century BCE that the ancient Greek calendars adopted a numerical system for naming months.
[3] The newly numerical calendars were also created in regions federated from the leagues of Phokis, Ozolian Locris, and Akhaia.
[3] Below are fifteen regions of the ancient Greek world and the corresponding information of the yearly calendar.
In the following tables the month names used in each Greek-speaking city are laid out with Athenian Greek letters (not necessarily how they were spelled in the city they were used in) transliterated into English letters, and with a leading ordinal number column.
The ordinal column is mostly for reference, and should not be read too literally: Different cities started their calendar year at different points in the solar year, and the month-numbers do not (necessarily) reflect the start date, which for some cities is not known.
Not all of the calendars are equally well-known, and confidence and uncertainties are discussed under individual headings, below.
[2] Occasionally, the Attic calendar would be thirteen months and have an intercalary year to keep the festivals aligned with the differing seasons.
[2] Additionally, the Attic calendar created extra days to have the festivals align with the lunar cycle.
The main reason this calendar existed was to keep track of the financial transactions within the Assembly.
Hesiod's recollection of the months includes only one (Ληναιων – Lēnaiōn) and this does not appear on any of the other calendars associated with Boeotia.
This gap in information suggests to scholars a change in the organizing of months between the archaic and classic times in Boeotia.
As most other regions in Greece, Boeotia divided their calendar months into thirds, but had differing ways to count the days.
With such a diversity in how the months themselves were categorized, it is hard for historians to give a definitive answer on the calendar.
Pindar's work is left to interpretation, and as such, causes dispute among scholars to which version is correct.
The one conclusion that is well known depends upon the Elian calendar beginning at the time of the winter solstice.
It would be reasonable to conclude that Elis would follow this example also, which refutes the idea of beginning at the winter solstice.
Construction of the calendar was put into effect by a German born mathematician named Abraham Fraenkel, and appears to be the most widely accepted version of the order.
Additionally, only one date is confirmed and it corresponds to the month found in the Thronion calendar.
Earlier translations lean toward the dialect with alpha, while later ones use the koine form with eta.
Greek consonants are transliterated as usual for English: θ = "th"; ξ = "ks" or "x"; φ = "ph"; χ = "ch"; ψ = "ps".
Transliterations are letter-by-letter and do not attempt to reduce Greek spelling conventions to phonetically equivalent English.