The Coligny Calendar

The Coligny Calendar

1. Basics:

The Coligny calendar was unearthed in 1897 at Coligny, in France.  It consists of 16 columns inscribed on a sheet of bronze.  At the time of its discovery, it was in fragments.  Much of it is missing.  It is the longest single text in the Gaulish language.1 As we will see, the calendar is a thorough application of the Samos and Giamos principles applied to time.

The calendar consists of a cycle of five years, consisting of 62 months, 60 regular months and two intercalary months.  The intercalary months come at the beginning and the middle of the five year cycle, dividing it into two halves. Given the organization of the rest of the calendar, this probably means that the first half of the cycle was the dark half and the second the light half.2

2. The Year:

The year is divided into two halves, the first beginning with the month of Samonios, the second with the month of Giamonios. Probably, the first half of the year is the dark half, and the second of the light half, but there is some controversy about this.  The regular months, in order, are named:

  1. Samonios                        MAT
  2. Dumannios                     ANM
  3. Riuros                             MAT
  4. Anagantios                     ANM
  5. Ogron                              MAT
  6. Cutios                              MAT
  7. Giamonios                      ANM
  8. Simiuisonnios                MAT
  9. Equos                              ANM
  10. Elembiuos                      ANM
  11. Edrinios                          MAT
  12. Cantlos                           ANM

The intercalary month is termed Ciallos, and is inserted into the first year of the 5 year cycle before Samonios and into the third year of the cycle before Giamonios. There is a great deal of controversy among scholars as to the meanings of the names of the months, so I have not provided translations here.3

3. The Month:

Months come in two types, of 30 and 29 days respectively.  Months of 30 days are termed MAT on the calendar, and those of 29 days are termed ANM.  MAT is probably an abbreviation for the Gaulish word matti, meaning “good”, while ANM is an abbreviation for anmatti, meaning “not good”.  Thus, months themselves have good and ill significance.  Months are further divided into two halves, the first of 15 days, the second of 14 or 15 days depending on the month.  These are clearly light and dark halves, but it is unclear which is which.  The writings of the Roman historian and scholar Pliny suggest that the first half is the light half, and therefore the waxing moon, but some scholars do not accept this.  The change from one half of the month to another is marked by the word ATENOUX, which might be translated either as “renewal” or as “the returning night”.4

4. The Day:

Days were also marked with a variety of notations.  Most of these deal with the various counting schemes that keep the calendar on track with the lunar and solar cycles and are not of interest to us here.  Three of them do concern us.  Some days are marked with MD and others with AMB.  MD seems to many scholars to stand for matti dîuos, “good day”, 5 meaning a day of good omen.  AMB would appear, to most scholars, to stand for anmattis dîuos, “not-good day”.6  In addition to the above two notations, many days are marked with IVOS.  According to Olmsted, this means “festival”, and marks out holidays.  Luckily for us, IVOS days occur in regular clusters through the year.  Notably, Olmstead states that clusters occur from two to four days before and after the beginning of Samonios,Dumannios, Anagantios, Giamonios, and Elembiuos. Clusters also occur three to four days before and after the ATENOUX of Riuros, on the 9th of Simiuisonnios, and on the first three days and the 25th of Edrinios.7 It should be noted that days start at sunset.

5. Controversies:

There are many controversies surrounding the Coligny Calendar.  The most important is that scholars are not sure when the year begins.  We know that Samonios is the first month, but when is that?  There are three main schools of thought:

  • a. Some scholars, taking their cue from the Irish Samhain, place the beginning of Samonios around the beginning of November.  This would make the first half of the year the dark half, equating to winter.  This is supported by a curious fact: one of the months of the Coligny Calendar was named Ogronios. In several Greek calendars of this period there is a month named Agrionios located in February/March.  Greek culture was very prestigious to the pre-Roman-Conquest Gauls.  They used the Greek alphabet for many inscriptions, for example, and borrowed the Greek symposion or ritual drinking party into their own aristocratic feasting customs and, to some extent, ritual observance.  If Ogronios is a case of cultural borrowing, then it stands to reason that the year began in November, exactly as it did in Ireland.
  • b. Others are convinced that the name Samonios refers to summer time, and would prefer to start the calendar at the summer solstice.  This would again make the first half of the year the dark half, but it would equate to the waning sun and not the winter at all.  The names for the month of June in modern Welsh and Breton, which are derived from mediosaminos, “midsummer”, might suggest this, but there is absolutely no precedent in modern Celtic folklore for starting the year in summer.
  • c. Some place Samonios at or around the Winter Solstice, and assume the calendar drifted relative to the solar year in order to arrive at the placement of the Irish Samhain.  This is supported by the placement of the Irish cross-quarter holidays which do not equate to significant astronomical events.  Olmsted supports this view, but bases his opinion on an elaborate history of the calendar that is not supported by other scholars.8

There is also controversy over the beginning of the month.  The essential question is, did the month start on the new moon or the full moon?  Related is the question, which half is the light half?  Here there are two schools of thought:

  1. The moon started on the new moon, and ATENOUX marks the full moon.  This generally means that the first half of the month was the light half, equivalent to the waxing moon, and the second the dark half, equivalent to the waning moon.  Adherents of this theory generally translate ATENOUX by something like “the returning night”.
  2. The moon started on the full moon, and ATENOUX marks the new moon.  In this case, the first half of the month is the dark half, equivalent to the waning moon, and the second is the light half, equivalent to the waxing moon.  Adherents of this theory generally translate ATENOUX as something close to “renewal”.

The cases for these various schools of thought are generally very closely matched.  Nevertheless, we have to make choices in order to arrive at a working calendar.  I have made the following tentative choices to develop the working Gaulish calendar I will be presenting in the next column:

  1. We will start the year in November.  The evidence of the Greek month name and of the year of the modern Celtic peoples convince me that this option has slightly more going for it than the others.
  2. We will start the month at the new moon.  This is almost a purely arbitrary choice.  The two options here are almost exactly evenly matched.  But this makes the most intuitive sense to me, and so, given that we must make a choice, it is the choice we will make.

6. Additional Calendric Terminology:

Here are a grab bag of terms and abbreviations, which you, dear reader, will need to read the upcoming calendar. Some are modern reconstructions, a few are from the text of the calendar itself.

BG: Blêdani Galation, “Year of the Galatîs”, a more or less arbitrary era of my own creation, working backward from the date of Pliny, based on Garret Olmsted’s calculation that the Celtic calendar must have begun some 1000 years before Pliny observed it, and also taking into account the 25 year cycle of the calendar itself.9 The year 3034 BG begins in mid-November, 2015 CE.

Cemenolugrâ: Crescent, waxing moon, light half of month, derived from Welsh cefnlloer by an internet scholar named Bhrgowidon, working in the Celticaconlang Yahoo group.10

Senolugrâ: Waning moon, literally, “old moon”, a term of my own creation, from senos – “old”
and lugrâ – “moon”.11

IVOS: Festival.12

MD: matti dîuos, “good day”,13

AMB: anmatti dîuos, “not-good day”.14

Note that days are written in the format (date x of-Cemenolugrâ or of-Senolugrâ of month year), using Gaulish genitives. For both Cemenolugrâ and Senolugrâ, the genitive is –âs. For all months, the genitive is –i. Thus, the date January 5, 2016 would be written 10 Senolugrâs Dumanni, 3034, except after sunset, when it would be 11 Senolugrâs Dumanni, 3034.

  1. Ken Dowden, European Paganism: the Realities of Cult from Antiquity to the Middle Ages, pp. 197-199
  2.  Dowden, pp. 197-199
  3.  Alwyn and Brinley Rees, Celtic Heritage: Ancient Tradition in Ireland and Wales, pp. 85-87
  4.  Rees and Rees, pp. 86-89
  5.  Garrett Olmsted, A Definitive Reconstructed Text of the Coligny Calendar, p. 32, 38
  6.  Olmsted, A Definitive Reconstructed Text of the Coligny Calendar, p. 28
  7.  Olmsted, A Definitive Reconstructed Text of the Coligny Calendar, p. 35
  8.  Dowden, pp. 205-210
  9.  Olmstead, A Definitive Reconstructed Text of the Coligny Calendar, p.1; Matasovic, p. 69; McCone, pp. 94-102
  10.  Message in, dated Tue, 27 Aug 2002
  11.  Delmarre, pp. 269-270; Matasovic, p. 248
  12.  Olmstead, A Definitive Reconstructed Text of the Coligny Calendar, p.35
  13.  Olmsted, A Definitive Reconstructed Text of the Coligny Calendar, p.32, 38
  14.  Olmsted, A Definitive Reconstructed Text of the Coligny Calendar, p. 28
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  1. What do you think of the theory that the month actually began on [what Pliny considered] the 6th day of the moon, i.e. roughly the first quarter? As far as I can see Pliny is grammatically ambiguous and could be saying either that months are counted by the moon (without being more specific, but perhaps most likely meaning from the new moon) or that they are counted from the moon’s sixth day. I go back and forth on which is more likely in context. Starting from the new moon is intuitive, but starting from the first quarter seems in line with starting the year inbetween, rather than on, the solstices.

  2. As much a we are ‘trapped’ into using the conventional Gregorian calendar for the day to day, the idea of having a parallel system for planning out ritual practice, veneration and celebration is quite exciting. Really looking forward to the next article.


  3. Thanks Lee. When the next installment comes out, I hope you and yours can make some use of it.

  4. Sasha: You’ve answered your own question. The evidence is ambiguous and starting at the exact New Moon makes more intuitive sense.

  5. Just as a further alternative (since I have read many of the proposed reconstructions of the Coligny Calendar, and I generally distrust “Common Celtic” derivations/constructions, and Olmstead in particular, for various other reasons!). Given that Gaulish is a language, and thus likely a culture, which has more in common with Welsh than with Irish, and the Welsh major festival day yearly is Kalan Mai, what if–for the sake of argument–the Coligny Calendar began with a date analogous to that one, and thus the beginning of Summer itself, rather than “Summer’s End” (i.e. Samain) as with the Irish?

    There’s also the issue, touched upon in an Irish text or two, of whose time is more significant, i.e. human-world-time or Otherworld time…Samain for us is the beginning of Summer for the Otherworld, for example…so, Kalan Mai could be the “dark” part of the year in the Otherworld, even though it is the beginning of Summer in the human world.

    Anyway, just a few thoughts. 😉