History of September: The Start of Fall

Welcome September. Image by DALL-E 3

HISTORY OF SEPTEMBER

You may have noticed that September sounds like the Latin word for seven. And you’d be perceptive — septem is the Latin word for seven, and this month used to be the seventh month of the ancient Roman calendar.

This Latin numbering continues through the year’s remaining months, as highlighted below: octo/eight, novem/nine, decem/ten.

A Little Calendar History

Legend has it that this calendar, dating back to around 753 BC, was established by Romulus – the founder and first king of Rome – as I describe in my article on the Founding of Rome. The months counted up as follows:

1. Martius – 31 Days
2. Aprilis – 30 Days
3. Maius – 31 Days
4. Iunius – 30 Days
5. Quintilis – 31 Days
6. Sextilis – 30 Days
7. September – 30 Days
8. October – 31 Days
9. November – 30 Days
10. December – 30 Days

It Doesn’t Add Up

This adds up to only 304 days – about 61 days short of a solar year – leaving a chunk of winter that went uncounted. King Numa Pompilius reformed the calendar around 713 BC, adding January and February to the end of the year after December.

Calendar Going Imperial

As I’ve written before, Quintilis was renamed July in honor of Julius Caesar in 44 BC. Sextilis was renamed August in honor of Caesar Augustus in 8 BC. Emperor Commodus, son of Marcus Aurelius — made (in)famous by the movie Gladiator — renamed all 12 months after his own titles during his reign, but this was repealed (damnatio memoriae) after his assassination in AD 192.

Changes to the Roman calendar could only be made by the Pontifex Maximus, the high priest of the College of Pontiffs in ancient Rome. When Julius Caesar became pontifex maximus, he reformed the calendar by replacing the irregular intercalary month — once added to align the lunar calendar with the solar year — with a fixed 365-day year and a periodic leap day.

Calendar Reform

Gregorian calendar. Image: Science Source

The Julian Calendar reform began with Julius and was completed with Augustus. For over a millennium and a half, the Julian Calendar was in use until Pope Gregory XIII introduced what became known as the Gregorian (or Western or Christian) Calendar in 1582.

The Gregorian Calendar is now used almost universally as the civil calendar, not just in the West.

September as the Start of the Fall

September is the astronomical start of Fall, marked by the Autumnal Equinox. It used to be that September was when students returned to school for the Fall term, traditionally following harvest time. There are still half a dozen states in the U.S. that require school to begin no earlier than September 1, or at least after Labor Day.

During Charlemagne‘s time in the early 9th century, September was called “harvest month.” The Anglo-Saxons called it Gerstmonath or barley month, referring to its harvest, and the German-Swiss speakers call it Herbstmonat or “autumn month.”

See you in September.

Bill Petro, your friendly neighborhood historian
billpetro.com