Month Names Explained: How the Months Were Named
Ever wonder how the months got their names? We explain which deities, rulers, and numbers helped name January through December.
Quick Reference: Where the Month Names Come From
- Roman and Greek gods: January (Janus), March (Mars), May (Maia), June (Juno).
- Real Roman rulers: July (Julius Caesar), August (Augustus).
- A festival and a word: February (the februa cleansing rite), April (likely from a Latin root meaning “second”).
- Plain counting numbers: September (septem, 7), October (octo, 8), November (novem, 9), December (decem, 10).
- Why the numbers seem off: the Roman year once began in March, so the counts were correct before January moved to the front in 46 B.C.
Flip a calendar to any month in 2026 and you are reading a word that is more than two thousand years old. The names we say without thinking, January, February, on through December, carry the gods, rulers, and counting habits of ancient Rome. There are really three sources behind them: Greek and Roman deities, Roman rulers, and plain numbers. Here is how each one shaped the month, from January to December.
Month Names and Their Origins
- January is “the month of Janus,” the Roman god of beginnings and endings. Janus presided over doors and gates, fitting for the start of the year. He was usually shown with two faces, one looking backward and one forward, the way a new year looks at the old and the next at once.
- February, “the month of cleansing,” comes from februa, the name of a Roman purification festival held on the 15th of the month.
- March is named for Mars, the god of war and the planet that bears his name. In ancient Rome, several festivals of Mars fell in March, the earliest month when the weather turned mild enough to start a war. At one time March was the first month in the Roman calendar. The Romans changed the order of the months several times between the founding of Rome and the fall of the Roman Empire.
- April comes from the Latin Aprillis, a derivative of the Latin base apero-, meaning “second.” April carried that name because of the tweaking of the ancient Roman calendar, in which April was the second month. Some sources also tie the word to the Latin aperire, “to open,” for the season when buds and blossoms open.
- May springs from the Greek goddess Maia, daughter of Atlas and mother of Hermes. She was a nurturer and an earth goddess, which suits this springtime month, when flowers and crops burst forth.
- June descends from Juno, wife of Jupiter and the ancient Roman goddess of marriage and childbirth. Her tie to weddings is one reason June has long been a favorite month to marry.
- July was named in honor of Julius Caesar right after his assassination in 44 B.C., July being the month of his birth. July is the first month in the calendar to bear the name of a real person rather than a deity.
- August marks another Roman ruler enshrined in the calendar. In 8 B.C., the month Sextilis (“sixth”) was renamed for Augustus, nephew of Julius Caesar and the first emperor of Rome. The emperor’s name came from the Latin augustus, which gave us the adjective “august,” meaning “respected and impressive.”
- September, from the Latin septem (“seven”), reads as though it should be the seventh month of the year.
- The names for October (octo), November (novem), and December (decem) suggest they would be the eighth, ninth, and tenth months. And they once were, back when the Roman lunar calendar started the year in March at harvest time. All that changed in 46 B.C., when January became the first month of the new Julian calendar, pushing September through December to the ninth through twelfth months of the year.
The Three Sources Behind the Names
Group the twelve names and a clear pattern shows up. Four months honor gods, two honor rulers, two trace back to a festival or a word, and four are simply counting numbers that slipped out of place. The chart below sorts them so you can see at a glance which is which.
| Month | Source | Meaning or Namesake |
|---|---|---|
| January | Roman god | Janus, god of beginnings and endings |
| February | Festival | Februa, a Roman purification rite |
| March | Roman god | Mars, god of war |
| April | Latin word | From a root meaning “second,” tied to aperire, “to open” |
| May | Greek goddess | Maia, earth goddess and mother of Hermes |
| June | Roman goddess | Juno, goddess of marriage and childbirth |
| July | Roman ruler | Julius Caesar, born this month |
| August | Roman ruler | Augustus, first emperor of Rome |
| September | Number | Septem, “seven” |
| October | Number | Octo, “eight” |
| November | Number | Novem, “nine” |
| December | Number | Decem, “ten” |
Why the Numbered Months Are Off by Two
September through December are the puzzle of the calendar. Their Latin roots, septem, octo, novem, and decem, mean seven, eight, nine, and ten, yet today they sit ninth through twelfth. The answer is the changing Roman year. The old Roman calendar began in March, so counting forward from March made September the seventh month and December the tenth. When January and February were pulled to the front and January became the first month of the Julian calendar in 46 B.C., every numbered month shifted two slots without changing its name. The labels stuck, and we have lived with the mismatch ever since. Britannica’s overview of the month as a unit of time traces the same Roman reshuffling.
From the Roman Calendar to Ours
The month names survived a long road. The Roman lunar calendar started the year in March at harvest time, then changed shape more than once between the founding of Rome and the fall of the Empire. Julius Caesar’s reform in 46 B.C. set January at the front and gave us the Julian calendar, the backbone of the system we still read today. Two months later carried the names of rulers rather than gods, July for Caesar and August for Augustus, a sign that Rome’s leaders had grown powerful enough to write themselves into the year. The Almanac has tracked the sky and the seasons for more than two centuries, and the rhythm of those twelve months still anchors our calendar pages, from the spring equinox to the full Moon dates that mark each one.
Month Names: Frequently Asked Questions
How did the months of the year get their names?
The twelve month names come from three sources: Greek and Roman gods, Roman rulers, and plain numbers. January, March, May, and June honor the deities Janus, Mars, Maia, and Juno. July and August honor the rulers Julius Caesar and Augustus. September through December trace back to the Latin words for seven, eight, nine, and ten.
Why is September the ninth month when its name means seven?
The Roman calendar once started the year in March, which made September the seventh month, matching the Latin septem. When January became the first month of the Julian calendar in 46 B.C., every numbered month shifted two places forward but kept its old name. So September, October, November, and December still carry the words for seven, eight, nine, and ten.
Which months are named after real people?
July and August. July was named for Julius Caesar right after his assassination in 44 B.C., the month of his birth, and is the first month named for a real person rather than a deity. August was renamed in 8 B.C. from Sextilis to honor Augustus, the nephew of Julius Caesar and the first emperor of Rome.
What do January and February mean?
January is the month of Janus, the two-faced Roman god of beginnings and endings who watched over doors and gates. February, the month of cleansing, comes from februa, a Roman purification festival held on the 15th of the month.
Where do the spring month names come from?
March is named for Mars, the god of war and the planet. April comes from the Latin Aprillis, from a base meaning “second,” and is also linked to aperire, “to open,” for the blooming season. May honors the Greek goddess Maia, an earth goddess and the mother of Hermes. June descends from Juno, the Roman goddess of marriage and childbirth.
Why does the year start in January instead of March?
The early Roman calendar began the year in March. The reform that produced the Julian calendar in 46 B.C. moved January to the front, fittingly placing the year under Janus, the god of beginnings. That change is why the numbered months ended up two slots out of step with their Latin meanings.
Richard Lederer
Richard Lederer is a writer, speaker, and teacher best known for his books on word play and the English language and is a regular contributor to the Farmers' Almanac. You can visit his web site at Verbivore.
- Richard Lederer
The Roman calendar used to begin the year in March, the month of the spring equinox, but the change to January happened over half a century before Julius Caesar was born, basically for military reasons to accommodate all the rigmarole (religious, logistic, sometimes political) necessary before a commander embarked with an army to operate in areas farther from home, in particular the Hispanic peninsula. The first year in Roman history that began on 1 January was 153 BCE.
What did they do during the first two months?
I mean before they named them January and February…
The parts of the body
this comment section be wack
The calendar is a Gregorian calendar so to celebrate anything that is on the Gregorian calendar is going against God/Adonai you should be following the feast that are listed in the Torah/Bible those are the days that were set forth for us to honor and to remember and to celebrate by Adonai/God
I agree with you, but did you know that “The names that we use for the Jewish months are actually Babylonian in origin and were adopted by the Jews as of the time of the Babylonian exile in the sixth century BCE.“
The Torah that has been done away with tells us of much it tells us every thing we see today because it is a book of prophecy and the things for told are not done with just waiting to happen
I am a Christian, and it makes me wonder if God would approve of us celebrating New Years? Our calendar seems to be pagan, and if we celebrate new beginnings in January, wouldn’t we be honoring their god? Also, God says the beginning of the year starts in spring, not winter.
Romans have invented a lot of names
Can you refer to where it says this in the Bible, and let me know?
Hi Abraham, it does not that I’m aware of.
Read Exodus 12:1-3
It is time to check…
The world now becomes the true Babylon the great , under the leadership of the Romans… They influenced everything.
Take the warning of Revelation 18:4
Revelation 14:6-11
Stay faithful to Abba (Father) YAHAWAH, the Elohim of Abraham, Isaac, & Jacob(Israel) & to Yahawashi (Yahshua) our Messiah, our King till He returns…Go back to pure faith without leaven. Observe newmoons for it is where we can start a new beginning as a true worshipper in truth to Abba YAHAWAH & King Yahawashi…Be blessed?
Rosh Hashana (Jewish New Year) is in September
Spring and winter begin at different times depending where you are on the globe. The Romans were naming things relative to what they were experiencing. I would think that God would be understanding of our perspective and our ignorance.
Spare me the lecture
Hi
I am a Christian therefore I will be very glad to be given more information regarding roman history and Christianity.
Regards
Teke Moses Mokoena
I love the history that the farmers almanac presents!
The calendar’s history amazes me!