In 1897, the Gaulish Coligny Calendar was discovered in Coligny, Ain, France. The bronze calendar was found broken into 73 pieces, which together form a 5 foot wide, 3.5 foot high bronze tablet. When assembled, it displays a lunisolar calendar, which follows both moon phases and the time of solar year. It is believed that the calendar, dating back to the 2nd century AD, had been banned by the Romans as it indicated druidic practices. The calendar can now be found at the Gallo-Roman Museum of Lyon.
The age of the calendar has been estimated based upon the styling of the letters and images it contains. French archaeologist, J. Monard, has speculated that the druids created the calendar as a means of preserving the druid tradition of timekeeping at a time when the Julian calendar was being heavily promoted throughout the Roman Empire.
Druid were members of the educated, professional class among the Celtic peoples of Gaul, Britain, Ireland, and possibly elsewhere during the Iron Age. The druid class included law-speakers, poets and doctors, among other learned professions, although the best known among the druids were the religious leaders.
A calendar similar to the Coligny calendar was found nearby at Villards d’Heria. Both calendars follow the Contintental Celtic calendar. Through reconstruction, researchers have been able to determine that the calendar is a lunisolar calendar, focusing on the lunar month and the solar year. Scholars have disagreed as to whether a new month began with the new moon, full moon, or the first quarter moon. The lunar year was made up of 354 or 355 days.
There is dispute as to whether the calendar began in summer or autumn. The starting month, Samonios, is generally affiliated with Old Irish Samhain on October 31. However, Samon is Gaulish for summer. Like the modern calendar, the Coligny calendar is comprised of 12 months, with each month containing 29-30 days.
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