Unlike the modern understanding for measuring time and the application of the calendar, the ancient Hellenes did not use one common year calendar.

The Hellenes in ancient Greece have used a solar-lunar calendar, in which they included some months. According to Plato, the calendar ensured the “order” of performing the ceremonies of the different cults and the celebration of different seasons.

According to archeologist Sophia Kravaritou, doctor in religious anthropology sciences at the Sorbonne, the organization of the religious and political routine in ancient Greece has two characteristic data:

1.    The differences in names of the months in different cities; the existence of a big number of local holidays, which are connected to the cult of local heroes and events, which stress the peculiarities of every city and community when celebrated.

2.    The constant changes and the inclusion of new facts in relation to each historic period. To this we can add the exempt from rules new events, which were imposed by social and political changes.

For example, the Hellenes have used the solar-lunar calendar but in the course of few months, they used to add a 13^th month, which used to take the name of the previous one with the addition of “second,” in order for the 12 lunar months to balance out with one solar year or with the full cycle of the seasons.

About 130 local month names are known but one name can be used for different months in different cities. For example in 5 B.C., the Attic month Elafivolion (March/April) corresponded to the Spartan Artemisii, but on Dilos Island, Artemisii corresponded to Mounihionas (April/May) in Attica.

Sometimes events were lost in time. For example, when some hamlets on Mykonos Island united without an outer force in 2 B.C, they did not change the names of the months and the local hero cults, which were vital for the historic memory of those completely different towns.

When in 4 B.C. the tyrant Dionysius from Syracuse conquered Naxos Island, he changed the Ionian names of the months with Dorian ones. He also changed the name of the town to Tauromenius and this way he tried to redirect the historic memory.