The Celtic calendar is a compilation of pre-Christian Celtic systems of timekeeping, including the Gaulish Coligny calendar, used by Celtic countries to define the beginning and length of the day, the week, the month, the seasons, quarter days, and festivals.

Continental Celtic calendar

The

Gaulish Gaulish was an ancient Celtic language spoken in parts of Continental Europe before and during the period of the Roman Empire. In the narrow sense, Gaulish was the language of the Celts of Gaul (now France, Luxembourg, Belgium, most of Switze ...

Coligny calendar is the oldest known Celtic solar-lunar ritual calendar. It was discovered in Coligny, France, and is now on display in the Palais des Arts

Gallo-Roman Gallo-Roman culture was a consequence of the Romanization of Gauls under the rule of the Roman Empire. It was characterized by the Gaulish adoption or adaptation of Roman culture, language, morals and way of life in a uniquely Gaulish context ...

museum, Lyon. It dates from the end of the second century CE, when the Roman Empire imposed the use of the

Julian Calendar The Julian calendar, proposed by Roman consul Julius Caesar in 46 BC, was a reform of the Roman calendar. It took effect on , by edict. It was designed with the aid of Greek mathematicians and astronomers such as Sosigenes of Alexandri ...

Roman Gaul Roman Gaul refers to GaulThe territory of Gaul roughly corresponds to modern-day France, Belgium and Luxembourg, and adjacient parts of the Netherlands, Switzerland and Germany. under provincial rule in the Roman Empire from the 1st century ...

. The calendar was originally a single huge plate, but it survives only in fragments. It is inscribed in Gaulish with Latin characters and uses

Roman numerals Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers are written with combinations of letters from the Latin alphabet, ...

. The Coligny Calendar is an attempt to reconcile the cycles of the moon and sun, as is the modern

Gregorian calendar The Gregorian calendar is the calendar used in most parts of the world. It was introduced in October 1582 by Pope Gregory XIII as a modification of, and replacement for, the Julian calendar. The principal change was to space leap years d ...

. However, the Coligny calendar considers the phases of the moon to be important, and each month always begins with the same moon phase. The calendar uses a mathematical arrangement to keep a normal 12 month calendar in sync with the moon and keeps the whole system in sync by adding an

intercalary month Intercalation or embolism in timekeeping is the insertion of a leap day, week, or month into some calendar years to make the calendar follow the seasons or moon phases. Lunisolar calendars may require intercalations of both days and months. S ...

every years. The Coligny calendar registers a five-year cycle of 62

lunar month In lunar calendars, a lunar month is the time between two successive syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona, Middle Eastern, and Eur ...

s, divided into a "bright" and a "dark" fortnight (or half a moon cycle) each. The months were possibly taken to begin on the new moon, and a 13th

intercalary Intercalation may refer to: *Intercalation (chemistry), insertion of a molecule (or ion) into layered solids such as graphite *Intercalation (timekeeping), insertion of a leap day, week or month into some calendar years to make the calendar follo ...

month was added every two and a half years to align the lunations with the solar year. The astronomical format of the calendar year that the Coligny calendar represents may well be far older, as

calendar A calendar is a system of organizing days. This is done by giving names to periods of time, typically days, weeks, months and years. A date is the designation of a single and specific day within such a system. A calendar is also a phy ...

s are usually even more conservative than rites and

cult In modern English, ''cult'' is usually a pejorative term for a social group that is defined by its unusual religious, spiritual, or philosophical beliefs and rituals, or its common interest in a particular personality, object, or goal. Thi ...

s. The date of its inception is unknown, but correspondences of

Insular Celtic Insular Celtic languages are the group of Celtic languages of Brittany, Great Britain, Ireland, and the Isle of Man. All surviving Celtic languages are in the Insular group, including Breton, which is spoken on continental Europe in Brittany, ...

and

Continental Celtic The Continental Celtic languages are the now-extinct group of the Celtic languages that were spoken on the continent of Europe and in central Anatolia, as distinguished from the Insular Celtic languages of the British Isles and Brittany. ''Contine ...

calendars suggest that some early form may date to

Proto-Celtic Proto-Celtic, or Common Celtic, is the ancestral proto-language of all known Celtic languages, and a descendant of Proto-Indo-European. It is not attested in writing but has been partly reconstructed through the comparative method. Proto-Celt ...

times, roughly 800 B.C. The Coligny calendar achieves a complex synchronisation of the solar and lunar months. Whether it does this for philosophical or practical reasons, it points to a considerable degree of sophistication.

Medieval Irish and Welsh calendars

Among the

Insular Celts The Insular Celts were speakers of the Insular Celtic languages in the British Isles and Brittany. The term is mostly used for the Celtic peoples of the isles up until the early Middle Ages, covering the British– Irish Iron Age, Roman Britai ...

, the year was divided into a light half and a dark half. As the day was seen as beginning at sunset, so the year was seen as beginning with the arrival of the darkness, at Calan Gaeaf /

Samhain Samhain ( , , , ; gv, Sauin ) is a Gaelic festival on 1 NovemberÓ hÓgáin, Dáithí. ''Myth Legend and Romance: An Encyclopaedia of the Irish Folk Tradition''. Prentice Hall Press, 1991. p. 402. Quote: "The basic Irish division of the year ...

(around 1 November in the modern calendar). The light half of the year started at Calan Haf/ Bealtaine (around 1 May, modern calendar). This observance of festivals beginning the evening before the festival day is still seen in the celebrations and folkloric practices among the

Gaels The Gaels ( ; ga, Na Gaeil ; gd, Na Gàidheil ; gv, Ny Gaeil ) are an ethnolinguistic group native to Ireland, Scotland and the Isle of Man in the British Isles. They are associated with the Gaelic languages: a branch of the Celtic langua ...

, such as the traditions of '' Oíche Shamhna'' (Samhain Eve) among the Irish and ''Oidhche Shamhna'' among the Scots.

Julius Caesar Gaius Julius Caesar (; ; 12 July 100 BC – 15 March 44 BC), was a Roman general and statesman. A member of the First Triumvirate, Caesar led the Roman armies in the Gallic Wars before defeating his political rival Pompey in a civil war, an ...

said in his ''

Gallic Wars The Gallic Wars were waged between 58 and 50 BC by the Roman general Julius Caesar against the peoples of Gaul (present-day France, Belgium, Germany and Switzerland). Gallic, Germanic, and British tribes fought to defend their homel ...

'': " he Gaulish Celtskeep birthdays and the beginnings of months and years in such an order that the day follows the night." Longer periods were reckoned in nights, as in the surviving English term fortnight meaning two weeks, and the obsolete ''se'nnight'' meaning one week. The Laws of Hywel Dda (in editions surviving from the 12th and 13th centuries) make repeated references to periods of ''nine days'' (''nawfed dydd''), rather than the "eight nights" that make up the current word ''wythnos''.

Native calendar terms in Celtic languages

Many calendrical and time-keeping terms used in the medieval and modern Celtic languages were borrowed from Latin and reflect the influence of Roman culture and

Christianity Christianity is an Abrahamic monotheistic religion based on the life and teachings of Jesus of Nazareth. It is the world's largest and most widespread religion with roughly 2.38 billion followers representing one-third of the global popula ...

on the Insular Celts. The words borrowed include the month names ''Januarius'' (Old Irish ', Irish ''Eanáir'', Welsh '), ''Februarius'' (Old Irish ', Irish ''Feabhra'', Welsh '), ''Martius'' (Old Irish ', Welsh '), ''Aprilius'' (Old Irish ', Irish ''Aibreán'', Welsh '), ''Maius'' (Welsh '), ''Augustus'' (Old Irish ', Welsh '); the names for the days of the week, ''Solis'', ''Lunae'', ''Martis'', ''Mercurii'', ''Jovis'', ''Veneris'', ''Saturni''; the terms ''septimana'' "week" (Old Irish ', Breton ', Cornish '), ''kalendae'' "first day of the month" (Old Irish ', Welsh ', Breton '), ''tempore'' "time" (Welsh '), ''matutina'' "morning" (Cornish ', Irish ''maidin''), ''vespera'' "evening", ''nona'' "noon" (Welsh ', Irish ''nóin''), and ''ôra'' "hour" (Welsh ', Breton ', Irish ''uair''). A number of native Celtic terms survived the adoption of the Roman/Christian calendar, however:

In Neopaganism

In some

Neopagan Modern paganism, also known as contemporary paganism and neopaganism, is a term for a religion or family of religions influenced by the various historical pre-Christian beliefs of pre-modern peoples in Europe and adjacent areas of North Afric ...

religions, a "Celtic calendar" loosely based on that of

Medieval Ireland Ireland in the Middle Ages may refer to: *History of Ireland (400–800), Ireland in the early Middle Ages *History of Ireland (800–1169), Ireland in the high Middle Ages *History of Ireland (1169–1536), Ireland in the late Middle Ages See al ...

is observed for purposes of

ritual A ritual is a sequence of activities involving gestures, words, actions, or objects, performed according to a set sequence. Rituals may be prescribed by the traditions of a community, including a religious community. Rituals are characterized ...

. Adherents of Reconstructionist traditions may celebrate the four

Gaelic Gaelic is an adjective that means "pertaining to the Gaels". As a noun it refers to the group of languages spoken by the Gaels, or to any one of the languages individually. Gaelic languages are spoken in Ireland, Scotland, the Isle of Man, an ...

festivals of

, Imbolc,

Beltane Beltane () is the Gaelic May Day festival. Commonly observed on the first of May, the festival falls midway between the spring equinox and summer solstice in the northern hemisphere. The festival name is synonymous with the month marking the ...

, and Lughnasadh. Some eclectic Neopagans, such as

Wicca Wicca () is a modern Pagan religion. Scholars of religion categorise it as both a new religious movement and as part of the occultist stream of Western esotericism. It was developed in England during the first half of the 20th century and w ...

ns, combine the Gaelic fire festivals with solstices and equinox celebrations derived from non-Celtic cultures to produce the Wiccan modern

Wheel of the Year The Wheel of the Year is an annual cycle of seasonal festivals, observed by many modern pagans, consisting of the year's chief solar events (solstices and equinoxes) and the midpoints between them. While names for each festival vary among di ...

. Some eclectic Neopagans are also influenced by

Robert Graves Captain Robert von Ranke Graves (24 July 1895 – 7 December 1985) was a British poet, historical novelist and critic. His father was Alfred Perceval Graves, a celebrated Irish poet and figure in the Gaelic revival; they were both Celt ...

' "Celtic Tree Calendar", which has no foundation in historical calendars or actual ancient Celtic Astrology, instead being derived from Graves' extrapolation of ''The Song of Amergin''.

Continental Celtic calendar

Medieval Irish and Welsh calendars

Native calendar terms in Celtic languages

In Neopaganism

See also

References

Further reading