Celtic calendar


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 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 museum, Lyon. It dates from the end of the second century CE, when the Roman Empire imposed the use of the Julian Calendar in Roman Gaul. 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.
The Coligny Calendar is an attempt to reconcile the cycles of the moon and sun, as is the modern Gregorian calendar. 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 every years. The Coligny calendar registers a five-year cycle of 62 lunar months, divided into a "bright" and a "dark" fortnight each. The months were possibly taken to begin on the new moon, and a 13th intercalary 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 calendars are usually even more conservative than rites and cults. The date of its inception is unknown, but correspondences of Insular Celtic and Continental Celtic calendars suggest that some early form may date to Proto-Celtic times, roughly 800 BCE. 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 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. The light half of the year started at Calan Haf/Bealtaine. This observance of festivals beginning the evening before the festival day is still seen in the celebrations and folkloric practices among the Gaels, such as the traditions of Oíche Shamhna among the Irish and Oidhche Shamhna among the Scots.
Julius Caesar said in his Gallic Wars: " keep 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 make repeated references to periods of nine days, 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 on the Insular Celts. The words borrowed include the month names Januarius, Februarius, Martius, Aprilius, Maius, Augustus ; the names for the days of the week, Solis, Lunae, Martis, Mercurii, Jovis, Veneris, Saturni; the terms septimana "week", kalendae "first day of the month", tempore "time", matutina "morning", vespera "evening", nona "noon", and ôra "hour".
A number of native Celtic terms survived the adoption of the Roman/Christian calendar, however:
TermProto-CelticGaulishOld/Middle IrishModern IrishScottish GaelicManxWelshCornishBreton
Day / 24-hour period*latįonlat lathelálà, lathalaagolau go + lau = very bright; golau = light
Day*diį-diu "day"día; indiu "today"dia, dé; inniu, inniubh, inniugh "today"dia; andiu "today"jee; joo "today"dydd; heddiw "today"; diwrnod "24-hour day period"dydh; hidhyw "today"deiz; hiziou "today"
Night*nokWt-, *ad-akWi-nox, noct- "-night"nocht, adaignocht, oíchenochd, oidhchenoght, oienoson, nosneth, nosneiz, noz
Week *oktu-nokWt- / *oktu-diį-wythnos "8-nights"eizhteiz "8-days"
Fortnight*kWenkWe-decam-nokWt-cóicthiges "15-"coicíscola-deug kegeeshpythefnos "15-nights"pemzektez
Month*mīss-mid mímímìosmeemismismiz
Year*blid-anī-bis bliadainbliainbliadhnableinblwydd, blwyddynbledhenbloavezh, bloaz
Season, Period of Time*ammn, *ammn-stero-, *ratio-, *pritu-ammanamm, aimser, ráitheaimsiràm, aimsir, ràithimbagh, emsheramser, prydamseramzer
Winter*gijamogiamo-gem, gemredgeimhreadhgeamhradhgeureygaeafgwavgoañv
Spring*ers-āko "end ", *ues-ant-ēn-, *ro-bertiā earrach, robartaearrachearracharraghgwanwyn, gwaintenreverzi
Summer*samo-samo-sam, samradsamhradhsamhradhsoureyhafhavhañv
Autumn*uφo-gijam-r- "under wintertime", *kintu-gijamo "beginning of winter", *sito- "deer-"fogamurfóghmhar, fómharfogharfouyrcynhaeaf, hydrefkydnyav/kynyav, hedrahere, diskar-amzer
May, May Day*kintu-sam?n- "beginning of summer"CétamainCèiteanCéideamhainCyntefin
June, Midsummer*medio-sam?n- "mid-summer"MithemMeitheamhMehefinMethevenMezeven
July*uφer-kwenno-samo- "end of summer"Gorffennaf

In Neopaganism

In some Neopagan religions, a "Celtic calendar" loosely based on that of Medieval Ireland is observed for purposes of ritual. Adherents of Reconstructionist traditions may celebrate the four Gaelic festivals of Samhain, Imbolc, Beltane and Lughnasadh.
Some eclectic Neopagans, such as Wiccans, combine the Gaelic fire festivals with solstices and equinox celebrations derived from non-Celtic cultures to produce the Wiccan modern Wheel of the Year. Some eclectic Neopagans are also influenced by Robert Graves' "Celtic Tree Calendar", which has no foundation in historical calendars or actual ancient Celtic Astrology, instead being derived from Graves' vision of The Song of Amergin.