Have you ever wondered why October is the 10th month when "oct" clearly means eight? The answer lies in one of history's most enduring calendar confusions that still affects us today.
Originally, the Roman calendar had only 10 months, starting with March (Martius). In this ancient system, October was indeed the 8th month, perfectly matching its Latin name derived from "octo" meaning eight. The calendar looked like this:
1. Martius (March)
2. Aprilis (April)
3. Maius (May)
4. Junius (June)
5. Quintilis (July)
6. Sextilis (August)
7. September (7th month)
8. October (8th month)
9. November (9th month)
10. December (10th month)
This 10-month calendar totaled only 304 days, leaving about 60 days of winter unaccounted for. Romans simply considered this period as "monthless" time.
The confusion began when King Numa Pompilius (around 713-673 BC) added two months to the beginning of the year: Ianuarius (January) and Februarius (February). This addition pushed all the numbered months forward by two positions, but their names remained unchanged.
So October, which had been the 8th month, became the 10th month but kept its "eight" name. The same thing happened to:
• September (from "septem" = 7) became the 9th month
• November (from "novem" = 9) became the 11th month
• December (from "decem" = 10) became the 12th month
This is why all these months seem "off by two" in our modern calendar. It's a 2,700-year-old naming convention that we still use today!
The Romans had several opportunities to fix this naming inconsistency but never did. Even Julius Caesar, when he reformed the calendar in 46 BC to create the Julian calendar, kept the traditional month names despite their mathematical incorrectness.
Interestingly, July and August were originally called Quintilis (5th) and Sextilis (6th), but were later renamed to honor Julius Caesar and Augustus Caesar respectively. These are the only months that escaped the "off by two" problem because they were completely renamed rather than just repositioned.
Today, this ancient Roman calendar quirk serves as a daily reminder of how historical decisions can echo through millennia, embedded so deeply in our culture that we accept the mathematical inconsistency without question.