December wasn’t always the twelfth month of the year

Armchair linguists might know that the Latin word “decem” means “ten,” which is a little curious given that December is the twelfth month of the year.

So why isn’t December the tenth month of the year? Like other months on the modern calendar, including October and November, December once occupied a different place on the calendar, namely the Julian calendar that was used prior to the adoption of the Gregorian calendar.

Back then, December was the tenth month on the calendar. Though its position changed when the Gregorian calendar was adopted, its name remained the same.