First lets talk about the Coligny Calendar

The Coligny Calendar, found in Coligny, Ain, France in 1897, is indeed a great treasure. Much debate is spent on when the calendar starts its months and years. It’s one of the few things we have found that the Gauls left behind. When the months fall is somewhat constant. There are twelve months that appear every year, and out of every five years, the first and third year have a thirteenth, intercalary month.

The normal twelve months are as follows:

Samonios (May-June)

Dumanios (June-July)

Riuros (July-August)

Anagantios (August-September)

Ogronios (September-October)

Cutios (October-November)

Giamonios (November-December)

Simiuisonna (December-January)

Equos (January-February)

Elembiuos (February-March)

Aedrinios (March-April)

Cantlos (April-May)

(Some start the year at with Samonios in November-December.)

The intercalary months are:

Quimonios (before Samonios in the first year of a five year cycle)

Rantaranos (before Giamonios in the third year of a five year cycle)

The months are divided in halves, the first half is 15 days, the second either 15 or 14. This is because months alternate between 30 and 29 days. The months start in the first quarter moon, centering the full and new moons in each half. (Some say it starts at the new moon.) They years repeat in a cycle every five years. Again, much debate surrounds the calendar, a workable synopsis is all that can reasonably be provided in such an introduction.


Holidays are very important in looser, variant customs like Gaulish Polytheism. In the sense that they have the potential to bring folks of many disparate customs together. Much as we see in other customs. Though, with many other things in Gaulish Polytheism, there isn’t a universal set of holidays people observe. To cover them all would be exhaustive. Here is a sampling of a full set of holidays that uses the Coligny Calendar to determine the dates. The names of all but one are not named on the calendar.

Holidays are assumed by clusters of days, lasting about a week, and single days. On the calendar, these days are marked with the term “IVOS”, thought to mean “feast, festival”. So, again, names of the holidays are recent as we don’t know what they were originally called. Save for one: Trinoxtion Samoni.

Here’s a list of holidays based on the “IVOS” clusters on the Coligny Calendar. However, one does not need to know the Coligny Calendar to celebrate the holidays. To provide a context so that one will always know when the holidays are, solstices, equinoxes, and lunar phases will be used as references. The holidays are as follows:

These are some of the holidays within Gaulish Polytheism

  • Nouiobledanî “New Year”
    • This will be the first quarter moon usually in the Gregorian month of May. Sometimes it will be in June.
  • Centusamos “Start of Summer”
    • Centusamos two first quarter moons before the summer solstice.
  • Samolitus “Summer Festival”
    • Samolitus first quarter moon before the summer solstice
  • Trinoxtion Samoni (“Three Nights of Summer”)
    • Always starts on 17 Samonios. Usually the third quarter moon closest to the summer solstice. if the closest third quarter moon is more than a week after the summer solstice, go with the third quarter moon before it.
  • Cerdâlitus (“Crafter Feast”)
    • Third quarter moon before the first quarter moon that is two first quarters after the summer solstice. Always the third quarter before the next holiday, Centumetâs.
  • Centumethâs “First Harvest”
    • Two first quarters after the Summer Solstice
  • Catu Alessiâs “Battle of Alessia”
    •  3rd of October
  • Centugiamos “Start of Winter”
    • Two first quarter moons before the winter solstice
  • Giamolitus “Winter Feast”
    • Full moon closest to the winter solstice
  • Biuiacolanos “Quickening”
    • Two first quarter moons after the winter solstice
  • Uisonnalitus “Spring Feast”
    • First sliver, closest to the vernal equinox

Find out more about these holidays above over at Bessus Nouiogalation

Also here is a awesome Coligny Calendar app to go with the above Holidays

Coligny Calendar app

  • Trinouxs Samoni “Three Nights of Samonios”
    • The new moon nearest November 1, or the night after the full moon nearest November 1.
    • Associated Deities: Sucellus, Nantosuelta, the Ancestors, Cernunnos, and Maponus.
  • Iwos Dumanni “The Festival Of Dummanios”
    • The new moon nearest December 1, or else the full moon nearest the Winter Solstice.
    • Associated Deities: Epona, Cernunnos, Maponus, the Anderoi (to be propitated, not worshipped, the Dusioi (ditto).
  • Iwos Brigantias “The Festival Of Brigantia”
    • The new moon nearest May 1.
    • Associated Deities: Brigantia.
  • Iwos Lugous “Festival Of Lugus”
    • The new moon nearest August 1.
    • Associated Deities: Lugus, Rosemerta.

Above is Segomaros Widugeni version you can find more about these Holidays in his book Ancient Fire on pages 96-108.