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TheIrish calendar is theGregorian calendar as it is in use inIreland, but also incorporating Irish cultural festivals and views of the division of the seasons, presumably inherited from earlierCeltic calendar traditions.

The traditional Irish Calendar usesAstronomical Timing, howeverMeteorological Timing is also used by organisations such as theMet Éireann.^[1] Both are in use in theRepublic of Ireland, however generally the Astronomical Calendar is the most commonly used.^[2]

In English-language Julian calendars and its derivatives, the months are based on names fromClassical mythology, such as the name "February" which derives from the Roman purification rite,Februa. In the Irish calendar, the names of the months in theIrish language refer toCeltic religion and mythology, and generally predate thearrival of Christianity. The words for May (Bealtaine), August (Lúnasa) and November (Samhain), are the names of Gaelicreligious festivals. In addition, the names for September (Meán Fómhair) and October (Deireadh Fómhair) translate directly as "middle of harvest" and "end of harvest". Christianity has also left its mark on the Irish months: the name for December (Nollaig) derives from Latinnatalicia'birthday', referring to the birth of Christ.^{[citation needed]}

• Winter (Geimhreadh) – November, December, January (Samhain, Nollaig, Eanáir)
• Spring (Earrach) – February, March, April (Imbolc, thenFeabhra, Márta, Aibreán)
• Summer (Samhradh) – May, June, July (Bealtaine, Meitheamh, Iúil)
• Autumn (Fómhar'Harvest') – August, September, October (Lúnasa, Meán Fómhair, Deireadh Fómhair)

Historical texts^[which?] suggest that, during Ireland'sGaelic era, the day began and ended atsunset.^[3] Through contact with theRomans, the seven-dayweek was borrowed bycontinentalCelts, and then spread to the people of Ireland.^[3] In Irish, four days of the week have names derived fromLatin, while the other three relate to thefasting done by early Gaelic Christians.^[4]

• Calendar of saints
• Celtic calendar
• Coligny calendar
• Gregorian calendar
• Liturgical year
• The Old Cows Days/The Days of the Brindled Cow

• Specific calendars
• Culture of Ireland
• Irish language
• Culture of Scotland
• Scottish Gaelic language
• Culture of the Isle of Man
• Gaelic culture

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• Articles that may contain original research from June 2015
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