This calendar attempts to follow the same patterns of symbols and markings as the original. Intercalary months are indicated as ambantaranos and postintercalary months are sequentially numbered. Right now this reconstruction doesn't always get some of the symbols right such as the triple marks, but it is otherwise mostly reliable, and the lunar phases and the holidays are high confidence. The Coligny calendar was written down by Druids, who carried on a long oral tradition of computing which days were important in which ways, and they used a complex system where notations and markings got swapped around, dragged along, and copied, sometimes affecting the day's entire notation and sometimes only affecting parts of it. That turns out to not be easy to code for, so some discrepancies are inevitable.
I've written this code to reconstruct the calendar based on the information available from the Wikipedia page, which in turn describes the patterns found by McKay et al (2016, 2018, 2020, 2022).
Important: This is a modern interpretation of the Gaulish calendar. This section is not guaranteed to be accurate to the way the ancients practiced ritual and magical timekeeping, since that knowledge has been lost. This is one individual's interpretation based on the available evidence and a bit of guesswork.
ponc dīus eđđi ambrixtios
ni eđđi-i matis rīs brixtī
toncnamanā uātoues-c ni ancont sondiobi
eti mā dīus eđđi matis
brixtiā bissiet robelā inte couīron
When the day is marked D AMBRIX,
It is not favorable to magic.
Spells and prophecies won't succeed on such a day.
But if the day is marked M D,
Magic will be powerful indeed.
trīes lergoi uennānt ponc brixtiā eđđi auuesseiā
ixse ambrixtiobi dīoubi
molātus rodiaunos dēuobi
cintus rīs bāregū •
allos rīs similātiū •
tritos rīs areuesprū
moisamos lergos bissiet amman matīsamon brixtī
pissoni ossimiās cebenolugriās • brixtin gniíomos in areuesprī
rīs regī lugriās tras tedrās noxtās dubuiās
Three marks tell when magic is to be done
Or on days marked AMB,
When to honor the Deuoi
One for morning, another for midday, and a third for afternoon.
The largest mark will be best time for magic.
With the sighting of the last crescent moon, we do a magic ritual in the afternoon
To guide the moon through three nights of darkness.
ponc dīus eđđi prinnī loudinos
nabocatíis catiet slattās rīs uātou
ponc dīus eđđi prinnī lagetos
slattās sent anateiās in tancē
eti ponc noxs eđđi īnis rīs
uātis areuocanet inte đirās
When a day is marked PRINNI LOVDIN,
A seer throws sticks for prophesy.
When a day is marked PRINNI LAG,
The sticks are to remain still.
But when a night is marked INIS R,
A seer prophesizes by the stars.
As to the exact means of performing divinations and rituals, the ancients haven't left us very much to go on, since so much of this knowledge would have been sacred and they would have refrained from writing about it or risking it being known to non-Druids. However, descriptions of Celtic rituals do exist in ancient documents, and some modern practitioners have reconstructed or innovated rituals and means of divination. I am not affiliated with any of the below sites or groups; this is just a reference:
Feel free to select from the above list whichever practices are right for you.
pempe dīūs • ponc Cantlos dīuedet eti Samonios ceniet • gniíomos-nīs Īuon Samonion
nauan dīūs • ponc Samonios dīuedet eti Dumannios ceniet • gniíomos-nīs Īuon Dumannion
sondiē ammani readdāmos Dēuobi ernamos-c
dīū sepu atenolugrin Dumanniē • indomos indauion in tegobi anson
oxtū dīūs in Riurē • gniíomos-nīs Īuon Riuron
sondios eđđi amman cintous rētous • eđic depromos nos suesin lanūs rosmertibi
oxtū dīūs • ponc Riuros dīuedet eti Anaganntios ceniet • gniíomos-nīs Īuon Anaganntion
gniíomos-nīs Dēuobi rātā molātūs-c petātūs-c • pon ne pissiont-íis-nīs amman
suexs dīūs • ponc Cutios dīuedet eti Giamonios ceniet • gniíomos-nīs Īuon Giamonion
are lanolugriā in Simiuisonnī eđđi dīus tīocobrixtios
sepu lanolugrīn in Simiuisonnī gniíomos-nīs īuon santerī ammēs are uisonniā
oxtū ixse nauan dīūs • ponc Equos dīuedet eti Elembiuos ceniet • gniíomos-nīs Īuon Elembiuon
Dēuoi eti andegentī anatiā ate monīntor eti bitus atebiuet
rodīmos-nīs Dēuobi brātun molātun-c rīs cateiātou eionon
trīs dīūs • pennū Aedrinī • gniíomos-nīs Īuon Aedrinios
indomos-nīs aidu agannton sīnī buiaunī cliíarin
lanolugrī Aedrinī • eđđi dīūs tīocobrixtios • santerē ammani are samū
cintuī cebenolugriā aridercī Aedrinī • gniíomos-nīs īuon
atenolugrī Cantlī • eđđi dīūs tīocobrixtios
Here is a resource linking to different Gaulish communities with information about their celebrations of īuoi.
The regular (i.e. not intercalary) months follow a pattern where the names of each opposite pair contrasts in some way:
Samonios, the first month of the summer season, means something like "summery" or "of summer", and contrasts with Giamonios, the first month of the winter season, meaning "wintry" or "of winter".
Dumannios, the second summer month, is widely believed to have to do with fumigation, while Simiuisonna, the second winter month, is believed to mean "half-spring". The contrast is not obvious, but can be explained by Dumannios pertaining more to smoke from sacrificial pyres, and the contrast could be seen as having to do with the birth/death cycle.
Riuros, the third summer month, called "fat month", is a time of plenty, a time for reducing activity, while Equos, the third winter month, is a time for equestrian activities and increasing activity. Riuros has a mid-month fattening-up feast, while Equos emphasizes the importance of work.
The fourth summer month Anaganntios means "not for worship", and can be identified with the Greek concept of the "dog days", a particularly hot and inauspicious time of year. Elembiuos can be parsed as elu-en-biuos, meaning something along the lines of "many into living" or even "many incarnated". The ancient Gauls believed that Deuoi and divine spirits animated every natural object and phenomenon, so in that context it makes sense for Anaganntios to be a time when the Deuoi and nature spirits are removed in some way from the natural world, while its opposite Elembiuos would be the time when nature is most greatly inspirited.
Ogronios the fifth summer month is obviously named for ougros, coldness, contrasting with Aedrinios the fifth winter month, having to do with fire or warmth. The contrast is easy to see; Ogronios is when the weather starts cooling down, while Aedrinios is when the weather warms up again.
Cutios, the final summer month, is named for the voice and is a time of invocations. Its counterpart Cantlos is named for chanting, singing, and music. Invocations are private rituals expressing humble piety to the Deuoi, while the time of music and singing suggests gregarious festive celebration.
End interpretation and guesswork.MAT and ANM next to the name of the month: This indicates whether the month is considered auspicious or inauspicious. MAT months typically have 30 days while ANM months usually have 29 days, and the Gauls believed that even numbers were auspicious (matis), and odd numbers inauspicious (anmatis), so they labeled their months as MAT or ANM accordingly. However, there are exceptions since Equos is always ANM but sometimes has 30 days, and the intercalary months are always MAT even though Quīmonios only has 29 days.
ATENOUX, DIVERTOMV: Atenouxs literally means renewal, and indicates that after the 15th day the month is renewed for another 14 or 15 days. If a month has 30 days, it counts from day I to day XV, undergoes atenouxs, then counts from I to XV again. But if a month has only 29 days, then after atenouxs it only counts up to XIIII, and the last position is marked "diuertomu" (literally no summit) as a placeholder to indicate that no day occurs in that position.
IVOS, SINDIV IVOS, and TIOCOBRIXTIO: The word īuos means holiday, and the calendar identifies certain days as īuoi. A few types of īuoi are indicated. Four are multi-day festivals that mark the change of seasons, while other festivals perhaps have ceremonial themes. Then aside from the multi-day festivals there are six single-day holidays. Three days are marked "holiday today" (sindīū īuos), and would have been very important days to the Gauls. Finally, the three days marked tīocobrixtio[s] might have something to do with magic (tīo-co-brixtiā), or with law and justice (tīo-com-rextiā).
For 12 months after an intercalary month, all īuoi and tīocobrixtoi are moved up a month, e.g. summer to autumn between Dumannios and Riuros in years with a Quīmonios.
D, M D, N, AMB: The column of mostly Ds indicates whether the daylight hours (dīus, pronounced as two syllables) or nighttime hours (noxs) were considered more relevant to the day (lation). If a day is marked M D, then it is considered an auspicious day (matis dīus). A day marked AMB, short for D AMBRIX RI, was considered inauspicious, perhaps for purposes of magic (brixtiā). Note that it is possible for a day to be marked M D AMB, apparently meaning that it is an auspicious day for some things but not for others.
Triple Marks: While the meaning of the triple marks is uncertain, they occur only on days marked D and never on days marked N, indicating that they pretain to daylight hours only. Most likely they divide the day into three sections. They tend to occur in groups of three with three blank days between them, following a distinctive pattern where the first matis month (Samonios) has triple marks beginning on days 1, 7, 13, etc., the second matis month (Riuros) on days 2, 8, 14, etc., however certain other markings override the triple marks, causing them to sometimes appear in pairs or alone. The three intervening blank days may symbolize division of nighttime into three sections. A clue to the meaning of the triple marks is that the 21st of each month, corresponding to the last visible sliver of crescent moon, always includes a triple mark with the third member indicated, whether or not a triple mark would otherwise be expected there and whether or not one of the other members is indicated. Triple marks only occur if there is enough time to complete the full set of all three without exceeding day 30 or crossing an atenouxs. Otherwise if a set of triple marks would begin before the start of the month, it is omitted; if a set begins after day 28 or before atenouxs and after day 13, then the days' D column changes to NSDS, DSNS, or N.
INIS R: The meaning of this abbreviation is unknown, but its absence during full moon may mean that it has something to do with divination by the stars. Its presence changes the day's D to an N, along with all the effects resulting from the lack of a D. Its distribution doesn't follow an obvious pattern, although it is much more frequent in the Samonios season vs. the Giamonios season, and it never coincides with any of the īuoi. The base pattern on INIS R, i.e. when it would occur if not for the various notation swaps, shows a few regularities: During the first half of each month it would only fall on days that would otherwise be AMB, except for the 10th day of the 10th month. For the first 7 months of the year it would occur 2 times in odd numbered months and 4 times in even numbered months, after which it would occur only once a month and only on even numbered months. This pattern is obscured by the swapping of day notations between months.
PRINNI LOVDIN, PRINNI LAGET: The meaning of these abbreviations is not certain, but it is thought that the former may be days in which one must throw wooden wands for purposes of divination, and the latter may be days in which the wands must not be used. PRINNI is probably a variant spelling of prennī, "of a tree", in this case referring to the wooden divination sticks. PRINNI LOVDIN only occurs in matis months, and PRINNI LAGET only in anmatis months. They follow part of the same pattern as the triple marks, e.g. days 1 and 7 of Samonios, 2 and 8 of Riuros, etc.
If the Gauls numbered their years, there doesn't seem to be any trace of a year number on the Coligny calendar. The surviving fragments do preserve a couple of numbers on at least the second intercalary month: MXIII and CCCLXXXV. The text actually reads SONNO CÍNGOS [A]MMAN-M-MXIII [...]LAT CCC LXXXV [...]ANTARAN-M. Sonnocingos would mean year or literally "sun march", and amman means time. This is followed by M and then MXIII, the latter perhaps representing the 13 months of that year (mīđ = month and XIII = 13). LAT stands for lation (day), and is followed by 385 in Roman numerals, meaning the year is 385 days long (30 days of Ciallos plus six matis months of 30 days plus five anmatis months of 29 days with 30 days in Equos). ANTARAN is a word fragment, with the top-right part of a preceding letter like B or R or S visible, and may be a fragment of *ambantaranos with the meaning of intercalary, literally "inserted between". So it would seem that neither number represents the year.
Interestingly, if MXIII were read as 1013, and if that were taken as the year number for year 3 of the calendar, then the age of the Coligny calendar would place its epoch around the time late Proto-Celtic was beginning to diverge into daughter languages. But that does not seem to be the intended meaning.
Rather than the usual method of counting years directly, and ending up with yet another large four digit number to represent the current year, and since it matters to the calendar which year of the 5-year cycle it is, I have opted to count 19-year Metonic cycles first, then 5-year Coligny cycles, then years. The first Coligny cycle of each Metonic cycle is missing its year 1, so the 19 years of the Metonic cycle are counted as 1-2 (Coligny 1 year 2) through 1-5, then 2-1 through 2-5, 3-1 through 3-5, and 4-1 through 4-5, making a total of 19 years.
Without any way to narrow down the exact year of the original calendar, I have opted to assign a new epoch based on a known historical event. Uercingetorixs united the Gauls in 52 BCE, leading to a victory at Gergovia that same year. Unfortunately this was also the same year as Uercingetorixs' defeat at Alesia. I have chosen that event to serve as the basis for the epoch for this website's modern calendar. In order that this calendar's 5-year cycle may align with that of the Coligny calendar by Bessus Nouiogalation in the current year 2024 CE at the time of this writing, I have adjusted the exact epoch accordingly. The victory at Gergovia actually takes place in either the year 0-2-3 or 0-2-4 in this calendar, with the 1 Samonios of 52 BCE being the first day of year 4 of Coligny cycle 2 of Metonic cycle zero or 0-2-4. That makes the Gregorian year 2024 CE equal to Metonic cycle 109, Coligny cycle 2, years 2-3. This makes it possible to write the date in a distinctive way such as 109-2-2-11-17 for 17 Aedrini of the year this web page was first created, or 106-2-5-02-29 for the original Moon landings, or 58-2-2-03-05 for the first appearance of the supernova SN 1054, or for the present day that you are reading this (or have printed it), using i1 for the Quīmonios intercalary month and i2 for the Ciallos intercalary month.
