Mounichion

The Attic calendar or Athenian calendar is the calendar that was in use in ancient Attica, the ancestral territory of the Athenian polis. It is sometimes called the Greek calendar because of Athens's cultural importance, but it is only one of many ancient Greek calendars.

Although relatively abundant, the evidence for the Attic calendar is still patchy and often contested. As it was well known in Athens and of little use outside Attica, no contemporary source set out to describe the system as a whole. Further, even during the well-sourced 5th and 4th centuries BC, the calendar underwent changes, not all perfectly understood. As such, any account given of it must be a tentative reconstrucion.

The Attic calendar was an exclusively local phenomenon, used to regulate the internal affairs of the Athenians, with little relevance to the outside world. For example, just across the border in Boeotia, the months had different names, and the year even began in midwinter. In Athens, the year began six months later, just after midsummer. Furthermore, while Greek months were supposed to begin with the first sighting of the new moon, it was determined locally and with a degree of variability. In many years, the months in the two communities would have more or less coincided, but there is no sign that they tried to keep the days of the month exactly aligned, as they would have seen no reason to do so.

The divide between these neighbouring calendars perhaps reflected the traditional hostility between the two communities. Had the Boeotians been speakers of an Ionic dialect, the one spoken in Athens, there would have been overlap in the names of months. An example is the island of Delos, where the calendar shared four out of twelve month-names with Athens, but not in the same places in the year. There, even though the island was under some degree of Athenian control from around 479 to 314 BC, the year started, as with the Boeotians, at midwinter.

Athenians lived under a number of simultaneous calendars that were used to fix days for different purposes. How much each calendar meant to individuals probably depended on how they lived. They may be set out as follows:

No complete list survives anywhere with all twelve months set out in order, but the following reconstruction is certain. The correlation suggested here between the Athenian months and those of the modern (Gregorian) calendar is loose, and, in some years, it might have been off by over a month.

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