This month’s name stems from Latin octo, “eight,” because this was the eighth month of the early Roman calendar. When the Romans converted to a 12 month calendar, the name October stuck despite that fact that it’s now the 10th month!
The early Roman calendar, thought to have been introduced by Rome’s first king, Romulus (around 753 b.c.) was a lunar calendar. This ancient timekeeping system contained these 10 months: Martius, Aprilis, Maius, Iunius, Quintilis, Sextilis, September, October (the eighth month), November, and December. Martius, Maius, Quintilis, and October contained 31 days, while the other months had 30, for a total of 304 days. In winter, the days were not counted for two lunar cycles.
It wasn’t until about 713 b.c. that a calendar reform, attributed to the second Roman king, Numa Pompilius, added the months Ianuarius and Februarius. Some historians think that both months were placed at the end of the year, while others believe that Ianuarius became the first month and Februarius the last. Later reforms organized the months as they are arranged today in the Gregorian calendar, whereby October became the 10th month in spite of its name.
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