The calendar’s giveaway is hiding in plain sight: September, October, November, and December come from the Latin numbers septem, octo, novem, and decem — seven, eight, nine, ten. They sit two places wrong because Rome’s year originally began in March; the numbered months were counted from there. When January became the year’s start, nobody renamed them, and the mislabeling has now survived over two thousand years of opportunities to fix it.
Last updated: July 22, 2026
The year opens with religion. January honors Janus, the two-faced god of doorways and beginnings, who looks simultaneously into the old year and the new. February takes its name from Februa, the purification rites Romans performed in the year’s final stretch. March belongs to Mars — not only war god but guardian of agriculture — marking when armies and farmers alike resumed work after winter.
Spring’s names are gentler and hazier. April may derive from aperire, “to open,” for budding plants — though scholars debate a link to Aphrodite. May is generally traced to Maia, a goddess of growth, and June to Juno, queen of the gods and protector of marriage — the origin of June weddings’ ancient prestige.
Then politics muscles in. The month once called Quintilis (“fifth”) was renamed Julius in 44 BCE to honor Julius Caesar, who was born in it and had just reformed the entire calendar. Sextilis (“sixth”) became Augustus in 8 BCE for his heir, the first emperor. Later emperors tried the same trick — Caligula renamed September “Germanicus,” Domitian claimed October as “Domitianus” — but those vanities died with their sponsors. Only the two founders’ months stuck.
Other cultures name months differently: the Islamic calendar’s Ramadan derives from a root meaning scorching heat; the Hebrew months were carried back from Babylon; many East Asian calendars simply number theirs — an honesty English abandoned when March stopped being month one.
You can watch several of those naming systems side by side in the world calendars panel at ellatime.com, where today’s date appears simultaneously in nine calendars — Roman gods, numbered months, and all.
Not everyone accepted the pagan roster. The Quakers, objecting to months and days named for gods, used plain numbering — “First Month” for January, “First Day” for Sunday — for centuries, and revolutionary France went furthest of all: its 1793 calendar renamed every month for weather and harvest, from Thermidor (heat) to Brumaire (fog) and Floréal (flowers). The republic’s months lasted thirteen years before Napoleon restored the Roman ones, whose two-thousand-year incumbency has so far beaten every challenger.
English absorbed the Roman names through centuries of Latin’s prestige, but Old English once had earthier ones of its own: the Venerable Bede recorded months like Þrimilce, “three-milkings,” when cows were milked thrice daily in lush May, and Blōtmōnaþ, “blood-month,” for November’s livestock slaughter before winter. Germany’s old names — Heumonat, hay month; Windmonat, wind month — followed the same farming logic. The Roman gods won the calendar, but the older names survive as a reminder that months began as descriptions of work, weather, and survival.
Twelve names, three thousand years of politics and prayer — and every one of them still punched into each date the calendars at ellatime.com display.
Related on Ellatime: How the Hebrew Calendar Adds a Whole Leap Month · The Hindu Panchang: Five Measurements in Every Single Day · What Islamic Year Is It? Understanding 1448 AH
Further reading: Encyclopaedia Britannica — Calendar
Editorial Note: This article was researched and written by the Ellatime editorial team. We fact-check our content and update it regularly. For questions or corrections, contact us.
Related read: Why Prayer Time Apps Disagree: Calculation Methods Explained.