The ancient Greek calendar: the months of Athens and the new moon
The months of the Attic calendar from Hekatombaion to Skirophorion, the noumenia, Hesiod's days of the month, the archons and the offended Moon of Clouds.
There was no single calendar in ancient Greece. Every city had its own, with different month names, a different start to the year and magistrates in charge of regulating it. The best known is that of Athens, reconstructed from inscriptions, classical authors and ancient commentators. It was a lunisolar calendar: the months followed the Moon, but the year began with the first new Moon after the summer solstice and stayed anchored to the seasons through added months.
The twelve Attic months
The Athenian months were Hekatombaion, Metageitnion, Boedromion, Pyanepsion, Maimakterion, Poseideon, Gamelion, Anthesterion, Elaphebolion, Mounichion, Thargelion and Skirophorion. The names derived largely from religious festivals: Hekatombaion from the hecatomb, the great sacrifice, Anthesterion from the Anthesteria, the festival of flowers and new wine, Thargelion from the Thargelia in honour of Apollo. When an extra month was needed, Poseideon was usually repeated.
In the month of Hekatombaion the Panathenaia were celebrated, which every four years took the solemn form of the Great Panathenaia; in Boedromion the Eleusinian Mysteries took place, and in Elaphebolion the City Dionysia with its theatre contests. The calendar was therefore above all a calendar of festivals, and knowing it meant knowing when and how to honour each of the city's gods.
The days of the month
The first day of the month was called noumenia, new moon. The following days were counted in three decades: the first of the waxing month, the second of the full month, the third of the waning month, in which days were often counted backwards towards the end. The last day was called «the old and new», because on it the old Moon gave way to the new, according to a formula already attributed to Solon.
Hesiod, in the Works and Days, devotes a section to the days of the month, stating which are favourable for sowing, marriage or shearing sheep, and calls them days that come from Zeus. It is a precious document, because it shows that as early as the archaic age the lunar division of the month carried moral and religious meanings alongside the practical ones linked to work in the fields.
Archons, adjustments and the Moon's complaints
The management of the calendar lay in the hands of magistrates, who could insert or remove days for political or ritual reasons. Some inscriptions of the Hellenistic age give double dates, one day according to the archon and one according to the god, that is, according to the Moon. Alongside the festival calendar, Athens also used an administrative calendar, divided into prytanies, the periods in which each tribe presided over the Council.
Aristophanes mocks these irregularities in Clouds, first staged in 423 BC: the chorus reports that the Moon is indignant because the Athenians no longer keep count of the days properly, so much so that the gods go without their dinner, having waited for a festival on the wrong day. It is a comic scene, but it presupposes an audience that knew the problem well.
It was in Athens, in 432 BC, that the astronomer Meton proposed a nineteen-year cycle to regulate the intercalary months. It is not clear whether the Athenian civil calendar ever adopted it systematically, but the cycle enjoyed great success among astronomers. The variety of Greek calendars remains an important lesson: for the Greeks, measuring time was a civic matter before it was a scientific one.