How were the months called by the ancient Greeks, and which was the 13th month?

You may have heard it or imagined it, but we can confirm that calendars in ancient Greece and specifically in ancient Athens were different than they are today.

Painting of the Thesmophoric procession by the American artist Francis Davis Millet.

This is because the ancient Greek calendar was the so-called lunar-solar with months that followed the phases of the moon.

In addition, they added one extra month. In fact, each Greek city had its own names for the months. So the Athenians, like other ancient peoples such as the Babylonians and the Chinese, used a calendar whose calendar months went hand in hand with the natural lunar months.

The names of the months were Hekatombaion, Metagitia, Voidromia, Pyanopsia, Maimaktiria, Poseideon, Gamilia, Anthestiria, Elafivolia, Mounichia, Thargelia, Skiroforia. Essentially, these names were taken from the main celebrations that took place during this time. And because each lunar month lasts 29.5 days, the Athenians added an extra 13th month every 3 years to keep the months in line with the seasons.

Also, the Athenians divided their years according to the number of tribes that had their names from mythical heroes. The 12 races corresponded to the 12 months.