Coligny calendar

Coligny calendar
Reconstruction of the Coligny calendar
Type	Plaque, lunisolar calendar
Material	Bronze
Height	78 cm (31 in)
Width	134.8 cm (53.1 in)
Writing	Gaulish language using Latin script
Created	2nd century CE
Discovered	1897 Coligny, Ain, France
Present location	Gallo-Roman Museum of Lyon-Fourvière, Lyon, France
Culture	Roman Gaul

The Coligny calendar is a bronze plaque with an inscribed calendar, made in Roman Gaul in the 2nd century CE. It lays out a 5-year cycle of a lunisolar calendar, each year with 12 lunar months. An intercalary month is inserted before each 2.5 years. It is the most important piece of evidence enabling the reconstruction of an ancient Celtic calendar.

The calendar was found in 1897 in France, in Coligny, Ain (near Lyon), along with broken pieces of a life-size bronze statue of a nude male holding a spear, likely meant to portray Mars, the Roman god of war.^[1] Approximately 40% of the original calendar remains in the form of fragments. It was engraved on a bronze tablet, preserved in 73 fragments, that was originally 134.8 cm wide by 78.0 cm high. With the rim attached the plate measured 52 by 32 unciae Drusianae (2.75 cm to the uncia). It is written in the Gaulish language with the Latin alphabet, using Roman square capitals and Roman numerals. Based on the style of lettering and the accompanying statue, the bronze plaque likely dates to the end of the second century CE, although copying errors indicate that the calendar itself is much older.^[2] It is now held at the Gallo-Roman Museum of Lyon-Fourvière.

Bronze statue found with the calendar, possibly Mars, reconstituted by A. André.

Eight small fragments of a similar calendar were found at the double-shrine of Villards-d'Héria. It does not have the holes of a peg calendar^[3] that the Coligny calendar does, but otherwise has the same notations. It is now held in the Musée d'Archéologie du Jura at Lons-le-Saunier.

List of months

The names of the twelve lunar year months are reconstructed as Samonios, Dumannios, Rivros, Anagantios, Ogronios, Cutios, Giamonios, Simivisonnios, Equos, Elembivios, Edrinios, and Cantlos. The names occur in the genitive form SAMONI, DVMANNI, RIVRI, etc. in the internal notations of the calendar. The name of the first intercalary month may be listed at the end of the month as QVIMON, possibly for Quimonios, the second is reconstructed as ...antaran, starting with either B, R or S.

Samonios refers to summer, from samo-. Xavier Delamarre and Ranko Matasović state that Samonios comes from Proto-Celtic *samoni- "assembly, (feast of the) first month of the year", perhaps "assembly of the living and dead".,^{[4]: 267 [5]: 322} though it potentially conflicts with the month of Giamonios which refers to Gaulish giamo- "winter".

Samonios and Giamonios divide the calendar into summer and winter seasons of six months, each season led off by a festival of several days marked with IVOS. This indicates an early version of the same traditional seasons as seen in later Celtic contexts: "For two divisions were formerly on the year, viz., summer from Beltaine (the first of May), and winter from Samuin to Beltaine".^[6]

Allowing for variations between lunar and solar years and aligning the month names to the solar year's seasons, Samonios may have begun on the first quarter moon around May–June^{[citation needed]}; if aligned to the modern Gaelic festivals Beltane, Lughnasadh, Samhain and Imbolc, Samonios might have begun around on the first quarter moon around April—May.

Order	Name	Days	Etymology	Interpretation
				Solar	Gaelic Festivals
I-1	Quimonios?	29/30?	Unknown meaning	Apr-May	Mar-Apr
1	Samonios	30	Gaulish samo- "summer".[4]: 267	May-Jun	Apr-May
2	Dumannios	29	Potential cognate with Latin fūmus from P.I.E. dʰuh₂mós. Delamarre suggests "month of fumigations".[4]: 154	Jun-Jul	Apr-May
3	Rivros	30	O.Ir. remor "stout, thick, fat", W. rhef "thick, stout; great, large". Delamarre suggests "fat month".	Jul-Aug	Jun-Jul
4	Anagantios	29	Delamarre[4] suggests "month of ritual ablutions".	Aug-Sep	Jul-Aug
5	Ogronios	30	Delamarre[4] suggests "month of cold/winter".	Sep-Oct	Aug-Sep
6	Cutios	30	Delamarre[4] suggests "month of invocations".	Oct-Nov	Sep-Oct
I-2	[.]antaran	30	Unknown meaning	Oct-Nov	Sep-Oct
7	Giamonios	29	Gaulish giamos, "winter",[a] compare O.Ir. mi gam "November", according to Cormac's Glossary.[7]	Nov-Dec	Oct-Nov
8	Simivisonnios	30	Simi could mean half: "half the course of the sun".[4]: 274	Dec-Jan	Nov-Dec
9	Equos	29/30	Possibly a month of horses or livestock.[4]: 165	Jan–Feb	Dec-Jan
10	Elembivios	29	Month of the stag.[4]: 161–162	Feb-Mar	Jan–Feb
11	Edrinios	30	O.Ir áed "fire, heat".[4]: 34	Mar-Apr	Feb-Mar
12	Cantlos	29	Delamarre suggests "month of chanting".	Apr-May	Mar-Apr

The lunar month

The Coligny calendar as reconstructed consisted of 16 columns and 4 rows, with two intercalary months given half a column each, resulting in a table of the 62 months of the 5-year cycle. Whether the 5 years of the calendar plaque is part of a Metonic cycle of 19 year or 30-year cycle, the full length of the calendar is still debated.

Y1 IC1 01

Y1 RIV 04

Y1 GIA 08

Y1 AED 12

Y2 RIV 16

Y2 GIA 20

Y2 AED 24

Y3 RIV 28

Y3 IC2 32

Y3 EQV 35

Y4 SAM 39

Y4 OGR 43

Y4 EQV 47

Y5 SAM 51

Y5 OGR 55

Y5 EQV 59

Y1 ANA 05

Y1 SIM 09

Y1 CAN 13

Y2 ANA 17

Y2 SIM 21

Y2 CAN 25

Y3 ANA 29

Y3 ELE 36

Y4 DVM 40

Y4 CVT 44

Y4 ELE 48

Y5 DVM 52

Y5 CVT 56

Y5 ELE 60

Y1 SAM 02

Y1 OGR 06

Y1 EQV 10

Y2 SAM 14

Y2 OGR 18

Y2 EQV 22

Y3 SAM 26

Y3 OGR 30

Y3 GIA 33

Y3 AED 37

Y4 RIV 41

Y4 GIA 45

Y4 AED 49

Y5 RIV 53

Y5 GIA 57

Y5 AED 61

Y1 DVM 03

Y1 CVT 07

Y1 ELE 11

Y2 DVM 15

Y2 CVT 19

Y2 ELE 23

Y3 DVM 27

Y3 CVT 31

Y3 SIM 34

Y3 CAN 38

Y4 ANA 42

Y4 SIM 46

Y4 CAN 50

Y5 ANA 54

Y5 SIM 58

Y5 CAN 62

Detail of Samonios (year 1).

Each lunar year has 12 lunar months, six 30 day months, five 29 days months and a 29/30 day variable month. As synodic months are 29.53 days long, the calendar may overcome this by removing a day from a 30-day Equos month.^[b] The length of Equos may have been decided by the sighting of the first quarter moon, which start months in the calendar.

The first intercalary month is in year 1 at the start of the year before Samonios, the second appears between Cutios and Giamonios in year 3 in the middle of the year. The second has 30 days, the first is contested on whether it has 29 or 30 days. Intercalary months have set copying patterns from days across the months throughout the 5-year cycle to form their day notations.

McKay proposes the first intercalary month had 29 days,^[11] as the "30th" day of a 29-day month Cantlos, in year 1 would copy DIVERTOMV, a non-existent day. Olmsted notes it may be 30 days stating it is marked as a MATV month, and the remaining portion of the broken-off second digit of the Roman numeral for the last day potentially has a slant for XV instead of XIIII.

The start of the lunar month

The calendar month is broken into two halves with the term ATENOVX^[c] between them. The first half-month has 15 days (called a cóicthiges 'fifteen-days' in Old Irish, coicís in modern Irish).^[13] The second half-month has either 15 days, or 14 days with the term DIVERTOMV placed over the space for the 15th day. The notation patterns act as though this 'virtual' 15th day is present.

Pliny reported that the Celtic month began on the '6th day of the new moon'.^[14]

The mistletoe, however, is but rarely found upon the oak; and when found, is gathered with rites replete with religious awe. This is done more particularly on the sixth day of the moon, the day which is the beginning of their months and years, as also of their ages, which, with them, are but thirty years. This day they select because the moon, though not yet in the middle of her course, has already considerable power and influence; and they call her by a name which signifies, in their language, the all-healing.

Classical writers counted from the day of the first visible moon, so the 6th day would be the first quarter moon, Day 1, the start of the calendar's month. The quarter moon with its D-shape is the only moment in the lunar phase that is easily identifiable by eye.^{[citation needed]} The internal notations of the calendar confirm Pliny's statement, with a focus on the middle triplet of days in each half-month, days 7-8-9 (the full moon) and days 7a-8a-9a (the dark invisible moon).

Full reconstruction

A full reconstruction of the calendar by McKay (2020)^[15] includes the latest information about the intercalary notations and the triple marks. Olmsted (2001)^[10] offers a previous reconstruction, which usefully aligns the notations with photographic images. RIG III (1986)^[16] presented an earlier in-depth description of terms with a reconstruction.

As a cycle of 19 years

If based on a Metonic cycle, this can be created with four 5-year cycles with the first year dropped and 30-day Equos months on Cycle years 1 and 5. All days and notations are lunisolar, moving within a 36-day range of a solar date.

Metonic Reconstruction

Month	Cycle 1					Cycle 2					Cycle 3					Cycle 4
	Y1 __	Y2 01	Y3 02	Y4 03	Y5 04	Y1 05	Y2 06	Y3 07	Y4 08	Y5 09	Y1 10	Y2 11	Y3 12	Y4 13	Y5 14	Y1 15	Y2 16	Y3 17	Y4 18	Y5 19
I-1	__	__	__	__	__	29	__	__	__	__	29	__	__	__	__	29	__	__	__	__
SAM	__	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30
DVM	__	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29
RIV	__	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30
ANA	__	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29
OGR	__	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30
CVT	__	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30
I-2	__	__	30	__	__	__	__	30	__	__	__	__	30	__	__	__	__	30	__	__
GIA	__	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29
SIM	__	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30
EQV	__	29	29	29	30	30	29	29	29	30	30	29	29	29	30	30	29	29	29	30
ELE	__	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29
AED	__	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30	30
CAN	__	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29	29

The Metonic cycle, being 6940 whole days long, overruns the sun by 0.398396 days and the moon by 0.311620 days. As dates track phases of the moon, this would require a 30-day Equos month to be reduced to 29 days around every 61 years. As the moon would finish 0.0868 days ahead of the sun, the calendar after 219 years becomes a day ahead, requiring a 30-day month skipped after 6,569 years, or a 29-day month skipped after 6,350 years.

As a cycle of 30 years

Garrett Olmsted's Reconstructed Coligny Calendar

The calendar can perform as a 30-year cycle, using six 5-year cycles with a 30-day intercalary month dropped once every 30 years.^[17] If part of a 30-year calendar, it overruns the lunar phase by 0.1515 days, requiring a day to be removed from a 30-day Equos roughly once every 198 years.

However, the internal months show a larger variation in accuracy for the lunar phase of nearly 48 hours (1.44 to −0.65), making the ability to track the lunar phase of 30-years notably less accurate. The lunar/solar difference is larger at 1.4172 days, requiring a 30-day month to be skipped every 198 years.

This relatively fast slippage against the solar year would also add to the already large lunisolar swing, for a total of 75 days before a possible adjustment, further aggravating the solar discrepancy, and displacing seasonal festivals by up to two and a half months.

Sample month

The month of SAMONIOS in year 2 is the only month without any missing fragments, preserving all its notations.^[18]: 182 Most patterns of notations are known and can be reasonably reconstructed,^[d] though their purpose or significance is not fully understood.

The title starts with M declaring it as a month, followed by the name and its type, thus M SAMON MAT reads as "M(onth) Samon(ios) Lucky/Good". Days are sorted in rows, with ATENOVX "Renewal" dividing the month in two halves. Each day has four columns for the peg-hole, Roman numeral, triple-mark, day type and any additional notations. The M of day type appears in the triple-mark column.

The count for the days are in Roman numerals with additive notation, after ATENOVX, the count is reset. The triple marks have either no value, ƚıı, ıƚı or ııƚ; some have M after the triple mark or in its place, which is part of the following day's type. Day types are vertically aligned with D "day" or N "night". Day notations that provide further information on whether days were swapped, additional notations for day type or festivals. The PRIN LOVDIN notation spans across type and notation.

Drawing of month 14 (Samonios of year 2) by de Ricci.^[19]

M SAMON MAT
I		N	DVMAN IVOS
II	ıƚı M	D	IVOS
III	ƚıı	D	DVM IVO
IIII	M	D
V		D	AMB
VI	M	D
VII		PRIN LOVDIN
VIII		D	DVM
VIIII	ııƚ M	D
X	M	D
XI		D	AMB
XII	M	D
XIII	ƚıı M	D
XIIII	ıƚı M	D
XV	ııƚ M	D
ATENOVX
I		D	DVMAN
II	ııƚ	D	TRINVXSAMO
III		D	AMB
IIII	ƚıı M	D
V	ıƚı	D	AMB
VI	ııƚ M	D
VII		D	AMB
VIII		N	INIS R
VIIII		N	INIS R
X	ƚıı M	D
XI	ıƚı	D	AMB IVOS
XII	ııƚ M	D	IVOS
XIII		D	AMB IVOS
XIIII	M	D	IVOS
XV		D	AMB IVOS

Calendar notations

Several different notations, each with their own pattern, are placed sequentially on the 12 lunar months of the calendar, interacting according to certain rules with the notations before them, often replacing them. After the basic notations are set, many days' notations are then moved to other days, creating visual chaos. Finally, the days of the intercalary months are filled with notations copied from certain days in the 12 yearly months.

The notations, their patterns and interactions have gradually over the last century been identified by several key researchers, and what follows is a general, but not comprehensive, overview of each notation.

Numbering the days

Each month has two halves. The first half has days numbered from I to XV (1 to 15). The second half has either I–XV (1–15), or I–XIIII (1–14) with the 15th day marked with DIVERTOMV.^[e] The term ATENOVX is placed between the two half-months. The patterns of the notations act as though the 30th day is always present. This means that in practice some months only have 29 days, but conceptually, all months have 30 days.

MAT and ANM months and their days

MAT and ANMAT months

Summer	1	2	3	4	5	6
	MAT	ANM	MAT	ANM	MAT	MAT
	SAM	DVM	RIV	ANA	OGR	CVT
Winter	7	8	9	10	11	12
	ANM	MAT	ANM	ANM	MAT	ANM
	GIA	SIM	EQV	ELE	AED	CAN

Six months are marked in their header as MAT "good, auspicious", and six as ANM[AT] "not good", based on comparisons with Middle Welsh mad^[20] and anfad^[21] and Old Irish mad and ni-mad..^[22]

The summer season has 4 MAT and 2 ANMAT months, the winter season has 2 and 4 respectively. MAT months have 30 days and ANMAT months have 29 days with the exception of Equos that can have 30 days in years 1 and 5.

Order of MAT and ANM months

Type
	1	2	3	4	5	6
MAT	SAM	RIV	OGR	CVT	SIM	AED
ANM	GIA	EQV	ELE	CAN	DVM	ANA

The order of the MAT and ANMAT months is determined by the seasons; MAT months start in Summer on Samonios and ANMAT months start in Winter on Giamonios. This order is used for determining the triple mark and PRINI LOVD/LAG notations across the days of the month.

MAT month days are initially assigned M D (or MD) "good/auspicious day", and ANMAT month days are initially assigned D "neutral day". The terms M D and D refer to daylight hours in apposition to N "night". Any notation with N overwrites the full daytime notation, including triple marks, M D, D and D AMB.

The notation D AMBRIX RI

the D AMB pattern (orange) for a lunar month

D AMBRIX RI, usually shortened to D AMB, denotes an inauspicious day. It occurs only on Days 5 and 11 in the upper half-month, that being the period when the moon is more than half full, so it's mostly left free of inauspicious days. In the second half-month, D AMB is placed on every odd numbered day except Day 1, but this is explained by the traditional view that the unit 1 is neither odd nor even.^[f] The use of odd numbers as inauspicious is also seen with most months of 29 days being ANMAT 'not good'. It is symptomatic of Celtic cultures, as the Romans held the reverse view, that odd numbers were auspicious.^[23]

The triple marks

the base pattern of the triple marks

The triple marks are a series of ogham-like marks. They are first lain down each month in triplets over three days, ƚıı, ıƚı, or ııƚ, followed by three days with none. As they only occur with days marked with D (for daytime), and never N (for nighttime), they likely divide the daytime into three divisions.^[g]

The triple marks are by far the most complex notations, composed of three main patterns. They do not always repeat across the years. The first pattern assigns possible triplet positions which start on the same offset as the first PRINI term in the month, moving down a day in each of the following MAT or ANM months. The first triplet starts on Days 1-2-3 of SAMONIOS in Year 1, Days 2-3-4 in RIVROS, and so on following the MAT sequence of months. The equivalent sequence starts on Days 1-2-3 of GIAMONIOS in Year 3 and follows the ANM months, so mirroring one intercalary period to the other.

A second pattern, again following the MAT/ANM sequence, determines which triplets of the first pattern will manifest from year to year. This means the triple mark on a day/month of one year may not be found on the same day/month in another year.

A third pattern adds another IIT on Day 21(6a), the last day of the visible moon, adding to another mark if already there, resulting in each Day 21 holding either TIT, ITT, or IIT.

the final triple marks of year 4 (after all exchanges)

The triple marks undergo many changes as other notations are added. Days with N forms of notation overwrite the whole 'day' notation, e.g. IIT MD becomes just N, while ITI D AMB becomes just N. Days are moved and exchanged, often overwritten and lost, intercalary borrowed days are marked with N, and so on. The result turns a complex pattern of triple marks into visual chaos.^[h]

The notations PRINI LOVD and PRINI LAG

MAT Months	SAM	RIV	OGR	CVT	SIM	AED	SAM	RIV	-
PRINI LOVD Days	1	2	3	4	5	6	7	8	-
ANMAT Months	GIA	EQV	ELE	CAN	DVM	ANA	GIA	EQV	ELE
PRINI LAG Days	1	2	3	4	5	6	7	8	9

Like the triple marks, PRINI LOVD and PRINI LAG have the same month offsets for MAT and ANM respectively. If it falls on a triple mark, it replaces it, along with any M D, D, or D AMB. The PRINI LOVD of SIM 5 is later overwritten by N INIS R. Exchanges will lead to some PRINI LOVD ending up in ANM months, and vice versa.

The notation N INIS R

the N INIS R pattern

The term N INIS R is scattered across the lunar year. The significance of its distribution is undiagnosed. All but three instances occur in the seven months of the SAMONIOS season plus the month of GIAMONIOS. It avoids the days marked with IVOS 'festival'. As it occurs on seven nights when the moon is absent in the sky (the dark moon of 7a-8a-9a), and avoids the critical moments of the full moon of day 8 and the first visible moon of day 10a, it possibly refers to prognostication associated with stars.

The notations IVOS and SINDIV IVOS

the notations IVOS, SINDIV IVOS, and TIOCOBRIXTIO

The term IVOS 'festival'^[i] occurs in several runs of days of between three and nine days each, considered to mark each day of a festival. In all but two cases these festivals run from the end of one month into the beginning of the next. Four of these IVOS runs break the year into four-quarters, just as the four main Celtic festivals do in historic times, only here they are centered on Day 1 every three lunar months, rather than Day 1 of every three solar months as today.

There are also three other IVOS festivals on the calendar.

The term SINDIV IVOS 'this day a festival', occurs only three times – DVM 2a, SIM 9, and AED 25. These three special festival days must indicate something of exceptional importance in the year.

The notation TIOCOBRIXTIO

TIOCOBRIXTIO is an exceptional term which only occurs on three days in the year – SIM 7, AED 8, and CAN 15. Whatever its significance, it marks days of exceptional importance. Olmsted explains it could be read as T(R)IOCO(NT)O-BRIXTIO "A day in place day 30", possibly substituting for the missing day 30 of Cantlos.

Movement of notations between days

At this point, most notations have been assigned their base position on the calendar. What happens next is a major feature of the calendar, the movement of one day's notations to a different day. This visually breaks up the patterns of the notations, making the calendar seem quite random. This exchanging of days according to several different patterns, is a major aspect of the calendar, involving a total of 870 days over 5 years.

EXCHANGES: swapping notations between two days

the pairs of swapped days

There are several patterns in which two days swap their notations.^[j]

• The first pattern only involves Day 1 in four pairs of months.
• The second pattern involves days other than Day 1, and uses a different set of four pairs of months to swap between. Days are swapped with the same day of a neighbouring month.
• A third pattern is called the anomalous swaps, where days are swapped between a different day of a month. This occurs just three times per year: between SAM 3 and SAM 2a, between RIV 4 and RIV 10a, and between RIV 8a and ANA 4.^[k]

examples of the same and different day swaps

As the notations of one day are moved to another, they take the information with them about their original position (presumably so that one day can be used to prognosticate for its swapped partner). As most movements are to the same day of the month, the day information is redundant, so only the month name (in the genitive) is added. But anomalous swaps between different days require both their original day name and the month to be added.^[l]

EXCHANGES: Dragging notations between months

Examples in YEAR 1

Dates	Pre-drag	Post-drag
7 GIA	PRINI LAG	MD SIMIVIS TIOCOBREXTIO
8 GIA	D	MD SIMIVIS
9 GIA	N INIS R	MD SIMIVIS SINDIV IVOS
7 SIM	MD TIOCOBREXTIO	D EQVI
8 SIM	MD	PRINI LAG EQVI
9 SIM	MD SINDIV IVOS	D EQVI
7 EQV	D	D ELEMB
8 EQV	PRINI LAG	D ELEMB
9 EQV	D EQVI	D ELEMB

For the 12 lunar months after an intercalary month, the notations of the triplet of days 7-8-9 (the full moon) and 7a-8a-9a (the dark moon) in each month are dragged sequentially upwards to the previous month, like beads on a string. Their original month name is then added to the notations.

Dragging IVOS in Year 1

Dates	28 OGR	29 OGR	30 OGR	01 CVT	02 CVT	03 CVT	28 CVT	29 CVT	30 CVT	01 GIA	02 GIA	03 GIA
Pre- Drag	D AMB	MD	D AMB	MD	MD	MD	D AMB IVOS	MD IVOS	D AMB IVOS	MD SIMI IVOS	MD IVOS	MD IVOS
Post- drag	D AMB IVOS	MD IVOS	D AMB IVOS	MD IVOS	MD IVOS	MD IVOS	D AMB ←	MD ←	D AMB ←	MD SIMI ←	D ←	D ←

The notation IVOS is also sequentially dragged upwards a month in the post-intercalary year. However, it does not take all the other notations with it. This keeps the festival runs marked with IVOS intact. The same also applies to SINDIV IVOS.

The notations of the intercalary months

days copied to the intercalary months

The notations on the days of the intercalary months are created by a complex series of copies and merges of notations from certain days in the normal lunar months. Each day of an intercalary month sequentially copies a lunar month and the same day number, with its source month name added. At first 30 days are copied, and for days 1 to 18, their day number is replaced with a single N at the copied site. Secondly, a sequence of days 1 to 6 is again copied from a different year, and these are merged with the first. Thirdly, the days 7-8-9 and 7a-8a-9a which have been dragged from the following month are again merged with the copied notations. At which point, the calendar's notations are complete.

Footnotes

1. "L'étymologie est transparent puisque le nom du mois et fait sur celui de l'hiver giamo-." — Delamarre (2003):^[4]: 179
   [The etymology is transparent since the name of the month is made on that of the winter "giamo-".]
2. Equos in years 1 and 5 is marked with 30 days; Olmsted notes the header above 2nd Intercalary month has LAT CCCLXXXV "385 days", with Equos in year 3 maybe having 30 days. With years 2 and 4 on lost fragments, early scholars struggled to fit values to Equos for creating a Metonic cycle; MacNeill^[8] suggested that Equos in years 2 and 4 may have only 28 days,^[8] while Olmsted suggested 28 days in year 2 and 29 days in year 4.^[9][10]
3. cf. Old Irish athnugud "renewal"^[12]
4. The notations of days in a month are not always the same as the other years in the calendar and cannot be simply copied across other months.
5. Because the day numbers are repeated in the upper and lower coicise, researchers use either the number with 'a' attached for the lower coicise, or continue on the sequence. For example, Day VI (6) in the lower coicise is given as either Day 6a or Day 21.
6. unus non-est numerus sed ab eo crescunt numeri 'one is not a number, but numbers grow from it'^[7]: 16
7. A trace of the pre-Christian division of the day into three may be found here.

   For this is how Conchobor spends his time of kingship since he assumed sovereignty: as soon as he arises, settling the cares and business of the province, thereafter dividing the day into three, the first third of the day spent watching the youths playing games and hurling, the second third spent in playing brandub and fidchell and the last third spent in consuming food and drink until sleep comes on them all, while minstrels and musicians are meanwhile lulling him to sleep.^[24]

8. For a full explanation of the patterns of the triple marks, see McKay (2018)^[25]
9. Thurneysen (1899)^[26]: 530 suggested IVOS means "festival", although the etymology is obscure. The word ivos is also the Celtic word for "yew" – Rhys (1910),^[27]: 52 cf. Ivo, īwaz, and Zavaroni^[28]: 97 suggested a meaning of "(con)junction", but neither meaning has found wide support.
10. Exchanged days always occur between neighbouring months, but are not always between MAT and ANM months
11. The anomalous swaps were partially identified by MacNeill in 1928,^[8]: 9 later by Duval & Pinault in 1986,^{[16]: 267–340} Olmsted in 1988,^[29] and McKay in 2018.^[25]: 95
12. The notation TRINVX SAMONI, found at SAM 2a, means that its notations were originally at SAMONIOS day 3 in the upper coicise. SAM 3 is the last day of the IVOS festival at the beginning of SAMONIOS, presumably the equivalent of the Beltaine festival. It is not associated with Samhain, being in the summer month of SAMONIOS. It is not a three-night festival, being explicitly marked as a daytime D 'day' and SINDIV IVOS 'festival this (one) day'.

References

1. Charles Picard, Le bronze de Coligny, in L. Rosenthal, "Florilège des musées" du Palais des Arts de Lyon, p. 9, Mairie de Lyon, [s.d.] (1920<>1932).
2. Duval, P.M. and Pinault, G., Recueil des inscriptions gauloises, Tome 3: Les Calendriers (Coligny, Villards d'Heria), CNRS, Paris, 1986, pp. 35–37.
3. Lehoux, D.R. (2000). Parapegmata: or Astrology, Weather, and Calendars in the Ancient World (PDF) (PhD thesis). Toronto, Canada: University of Toronto.
4. Delamarre, Xavier (2003). Dictionnaire de la langue gauloise: une approche linguistique du vieux-celtique continental (2nd ed.). Paris, FR: Editions Errance. ISBN 2-87772-237-6.
5. Matasović, Ranko (2009). Etymological Dictionary of Proto-Celtic. Brill. ISBN 978-90-04-17336-1.
6. Meyer (1888). "Wooing of Emer". Archaeological Review. 1. >
7. Cormac mac Cuillenán (c. 900). Stokes, Whitley (ed.). "Sanas Cormaic". Thesaurus Linguae Hibernicae. Dublin, IE: University College Dublin. Retrieved 2014-03-07.
   Russell, Paul; Arbuthnot, Sharon; Moran, Pádraic. "Early Irish Glossaries Database". University of Cambridge. Retrieved 2014-03-07.
   
8. MacNeill, Eóin (1928). "On the notation and chronology of the calendar of Coligny". Ériu. X: 1–67.
9. Olmsted, Garrett (1992). The Gaulish Calendar: A reconstruction from the bronze fragments from Coligny, with an analysis of its function as a highly accurate lunar-solar predictor, as well as an explanation of its terminology and development. Bonn, DE: R. Habelt. ISBN 3-7749-2530-5.
10. Garrett Olmsted, (2001) A Definitive Reconstructed Text of the Coligny Calendar ISBN 9780941694780
11. McKay, Helen T. (2016). "The Coligny calendar as a Metonic lunar calendar". Études celtiques. 42: 95–121. doi:10.3406/ecelt.2016.2471.
12. Toner, Gregory; Maxim Fomin; Grigory Bondarenko; Thomas Torma; Caoimhín Ó Dónaill; Hilary Lavelle, eds. (2007). "athnugud". eDIL: electronic Dictionary of the Irish Language. Dublin, IE: Royal Irish Academy. Retrieved 2023-02-28.
13. Toner, Gregory; Maxim Fomin; Grigory Bondarenko; Thomas Torma; Caoimhín Ó Dónaill; Hilary Lavelle, eds. (2007). "cóicthiges". eDIL: electronic Dictionary of the Irish Language. Dublin, IE: Royal Irish Academy. Retrieved 2023-02-28.
14. Pliny the Elder (1855). "Book 16, "the natural history of the forest trees" English translation". In Bostock, John; Riley, Henry T. (eds.). The Natural History. University of Chicago. "Original Latin". penelope. University of Chicago.
15. McKay, Helen (2020). "THE COLIGNY CALENDAR A FULL RECONSTRUCTION With MODERN DATES second cycle". academia.edu. Retrieved March 1, 2023.
16. Duval, Paul-Marie; Pinault, Georges, eds. (1986). Les calendriers de Coligny (73 fragments) et Villards d'Heria (8 fragments). Recueil des inscriptions gauloises. Vol. Tome 3. Paris, FR: Editions du CNRS. pp. 35–37.
17. Ricci (1898) ^{[full citation needed]}
18. Dottin (1920). La langue gauloise : grammaire, textes, et glossaire [The Gaulish Language: Grammar, texts, and glossary]. Vol. 53. pp. 182–191.
19. de Ricci, S. (December 1926). "Le calendrier celtique de Coligny". Journal des savants: 448–449.
20. Centre for Advanced Welsh & Celtic Studies, ed. (1921). "Geiriadur Prifysgol Cymru A Dictionary of the Welsh Language". Aberystwyth: Centre for Advanced Welsh & Celtic Studies. Retrieved 2023-02-28.
21. Centre for Advanced Welsh & Celtic Studies, ed. (1921). "Geiriadur Prifysgol Cymru A Dictionary of the Welsh Language". Aberystwyth: Centre for Advanced Welsh & Celtic Studies. Retrieved 2023-02-28.
22. Toner, Gregory; Maxim Fomin; Grigory Bondarenko; Thomas Torma; Caoimhín Ó Dónaill; Hilary Lavelle, eds. (2007). "mad". eDIL: electronic Dictionary of the Irish Language. Dublin, IE: Royal Irish Academy. Retrieved 2023-02-28.
23. Theodor Mommsen (1864). Dickson, William Purdie (ed.). The Period Anterior to the Abolition of the Monarchy. The History of Rome. Vol. 1. London: Richard Bentley.
24. O'Rahilly, Cecile, ed. (1967). Tain bo Cuailnge. Dublin Institute for Advanced Studies.
25. McKay, Helen (2018). "Defining the systematic patterns for the triple marks of the Coligny calendar". Études Celtiques. XLIV: 91–118. doi:10.3406/ecelt.2018.2182.
26. Thurneysen, Rudolf (1899). "Der Kalender von Coligny". Zeitschrift für celtische Philologie. 2: 523–544. doi:10.1515/zcph.1899.2.1.523. S2CID 188129133.
27. Rhys, John (1910). Notes on the Coligny Calendar Together with an Edition of the Reconstructed Calendar. From the Proceedings of the British Academy, Volume 4 (Report). Oxford: Oxford U Press.
28. Zavaroni, Adolfo (2007). On the structure and terminology of the Gaulish calendar (Report). British Series. Oxford: British Archaeological Reports.
29. Olmsted, Garrett (1988). "The use of ordinal numerals on the Gaulish Coligny calendar". The Journal of Indo-European Studies. 16: 296.

Bibliography

• Delamarre, Xavier (2003). Dictionnaire de la langue gauloise: une approche linguistique du vieux-celtique continental. 2nd edition, Paris, Editions Errance. ISBN 2-87772-237-6.
• Dottin, Georges, La langue gauloise : grammaire, textes et glossaire (1920) no. 53, pp. 172–207.
• Duval, Paul-Marie and Pinault, Georges (eds) (1986). Recueil des inscriptions gauloises (R.I.G.), Vol. 3: Les calendriers de Coligny (73 fragments) et Villards d'Heria (8 fragments). Paris, Editions du CNRS.
• Hitz, Hans-Rudolf (1991). Der gallo-lateinische Mond- und Sonnen-Kalender von Coligny.
• Joyce, P.W. (2000). "Old Celtic Romances". The pursuit of the Giolla Dacker and his horse. Wordsworth Editions Limited, London.
• Laine-Kerjean, C. (1943). "Le calendrier celtique". Zeitschrift für celtische Philologie, 23, pp. 249–84.
• Delamarre, Xavier (2003). La langue gauloise. Paris, Editions Errance. 2nd edition. ISBN 2-87772-224-4. Chapter 9 is titled "Un calendrier gaulois".
• Le Contel, Jean-Michel and Verdier, Paul (1997). Un calendrier celtique: le calendrier gaulois de Coligny. Paris, Editions Errance. ISBN 2-87772-136-1
• Mc Cluskey, Stephen C. (1990). "The Solar Year in the Calendar of Coligny". Études Celtiques, 27, pp. 163–74.
• McKay, Helen (2016). "The Coligny calendar as a Metonic lunar calendar". Études Celtiques, XLII, pp. 95–122.
• McKay, Helen (2018). "Defining the systematic patterns for the triple marks of the Coligny calendar". Études Celtiques, XLIV, pp. 91–118.
• McKay, Helen (2022). "Building the Intercalary Months of the Coligny calendar". Études Celtiques, XLVIII, pp. 55–78.
• Mac Neill, Eóin (1928). "On the notation and chronology of the Calendar of Coligny". Ériu, X, pp. 1–67.
• Monard, Joseph (1996). About the Coligny Calendar. privately published monograph.
• Monard, Joseph (1996). Découpage saisonnier de l'année celtique. privately published monograph.
• Monard, Joseph (1999). Histoire du calendrier gaulois : le calendrier de Coligny. Paris, Burillier. ISBN 2-912616-01-8
• Olmsted, Garrett (1992). The Gaulish calendar: a reconstruction from the bronze fragments from Coligny, with an analysis of its function as a highly accurate lunar-solar predictor, as well as an explanation of its terminology and development. Bonn: R. Habelt. ISBN 3-7749-2530-5
• Parisot, Jean-Paul (1985). "Les phases de la Lune et les saisons dans le calendrier de Coligny". Études indo-européennes, 13, pp. 1–18.
• Pinault, J. (1951). "Notes sur le vocabulaire gaulois, I. Les noms des mois du calendrier de Coligny". Ogam, XIII, pp. 143–154
• Rhys, John (1910). "The Coligny Calendar". Proceedings of the British Academy, 4, pp. 207–318.
• Thurneysen, Rudolf (1899). "Der Kalender von Coligny". Zeitschrift für celtische Philologie, 2, pp. 523–544
• Zavaroni, Adolfo (2007). On the structure and terminology of the Gaulish calendar, British Archaeological Reports British Series.

External links

• The Gallic calendar – Lugdunum Museum

46°23′N 5°21′E / 46.383°N 5.350°E / 46.383; 5.350