Have you ever wondered why September is called September? If its name clearly seems connected to the number seven, why is September the ninth month of the year? And was it really once the seventh month?
To understand why it is called September, we need to travel back to ancient Rome. The name we still use today preserves a fascinating trace of a calendar that was very different from ours. So, let’s discover why the month of September is called September and what changed over the centuries.
Table of Contents
- Why is September called September?
- What changed with January and February?
- Julius Caesar and the calendar reform
- From the Roman calendar to the Gregorian calendar
- September still tells an ancient story
Why is September called September?
September comes from the Latin September, which is connected to septem, meaning “seven”. The explanation is surprisingly simple: in the ancient Roman calendar, September really was the seventh month of the calendar.
According to Roman tradition, the earliest calendar attributed to Romulus contained ten months and had the year beginning in March. March was therefore the first month, followed by April, May and June.
Then came Quintilis, the fifth month; Sextilis, the sixth; September, the seventh; October, the eighth; November, the ninth; and December, the tenth.
This explains why they are called that. October comes from octo, meaning eight; November from novem, nine; and December from decem, ten. Their names preserve a linguistic memory of their original positions in the Roman calendar.
What changed with January and February?
So how did September move from seventh to ninth place?
The earliest history of the Roman calendar cannot be reconstructed in every detail, and much of what we know comes from later Roman tradition. Numa Pompilius, the second king of Rome, is traditionally associated with important changes to the calendar, including the organisation of January and February.
Over time, January became the beginning of the civil year. March consequently moved from first to third place, and September shifted from seventh to ninth.
Its name, however, remained unchanged.
This is the key to understanding why the month of September is called September: its position changed, but its traditional name survived.
Julius Caesar and the calendar reform
Another major change came with Julius Caesar. In 46 BC, he introduced an important calendar reform that took effect the following year. This created the Julian calendar, designed to correspond more accurately with the solar year.
Even this reform did not change September’s name.
Other months had a different fate. Quintilis was later renamed Iulius in honour of Julius Caesar, giving us July. Sextilis became Augustus in honour of Emperor Augustus, giving us August.
In these cases, a month takes its name from a historical figure, while September, October, November and December retained their ancient numerical names.
From the Roman calendar to the Gregorian calendar
In 1582, Pope Gregory XIII introduced another reform to correct the discrepancy that had gradually developed between the Julian calendar and the solar year. This created the Gregorian calendar, which forms the basis of the civil calendar now used across much of the world.
September remained the ninth month of the year, but its ancient name survived.
This is not as unusual as it might appear. Words can outlive the circumstances that originally created them. Once the name September had become established in everyday language, there was little reason to replace it.
September still tells an ancient story
We can now answer the question why is September called September? The name comes from the Latin septem, meaning “seven”, because September occupied seventh place when the Roman year was considered to begin in March.
As the calendar evolved and January and February came before March, September became the ninth month without changing its name. Neither the reforms associated with Julius Caesar nor the later introduction of the Gregorian calendar erased this ancient linguistic legacy.
So, the next time you see September on your calendar, remember that its name carries a small piece of history more than two thousand years old.
What do you think? Had you ever wondered why September seems to refer to the number seven? Tell us in the comments.
Practical tip: start counting the months from March and continue through December. You will immediately understand why September, October, November and December have the names they do.
This post is also available in: Italiano (Italian)