Ides of March: What the Roman Saying Really Means

“Beware the Ides of March.” It is a phrase embedded into our culture more deeply than “Remember the Alamo.” Every spring, as March 15th rolls around, the old warning surfaces again in headlines, classrooms, and casual conversation. But what does it actually mean? Should we be wary of the “Ides,” whatever they are? Here is the history behind the saying, the calendar that gave us the word, and the reason a single day in March still carries a shiver of dread more than 2,000 years later.

What Are The “Ides of March” Exactly?

Anyone who studied Julius Caesar, William Shakespeare’s tragic play about the assassination of the Roman dictator, knows the origin of “Beware the Ides of March” well enough. It was the warning an old seer gave Caesar, and one he would have done well to heed. But before we get to that, let us clarify what the “Ides” even are.

In simplest terms, the “Ides of March” refers to March 15th. The day had greater significance than just a random date on the calendar, though. To understand why, you have to step back into the way the Romans kept track of time, because it worked nothing like the months we flip through today.

The Countdown

Though our modern calendar is a direct descendant of the ancient Roman calendar, there were also many differences. For one thing, while we number the days of each month sequentially, from one to 30 or 31 (or 28 or 29, in the case of February), the Romans, who always loved a party, counted backward toward the next festival. Their calendar was literally a series of countdowns.

These countdowns moved toward one of three fixed points in each month: the Nones, which fell on the 5th or 7th, depending on the length of the month (March, May, July, and October were the longest months); the Ides on the 13th or 15th; and the Kalends, which began the following month. So the Roman calendar did not have a plain March 1 or April 5, but rather “five days until the Ides of June” or “ten days until the Kalends of October.”

Although Rome had moved away from a strictly lunar calendar by the time of Julius Caesar, these special days aligned roughly with the phases of the Moon. The month started on Kalends with a New Moon, the Nones fell during its Quarter phase, and the Ides marked the full Moon. If you want to see how those phases still line up through the year, our full Moon dates and times keep the old rhythm in plain view.

Because of its association with the full Moon, the Ides was considered a holy day for the god Jupiter and set aside for feasting and sacrifice. This was especially true of the Ides of March, one of the highest holy days of the year, which was special, even before it went down in infamy, because of its status as the first full Moon of the year.

Yes, you read that right. During Roman times, the first full Moon of the year occurred in March. And no, there were not fewer full Moons back then. The Ides of March was the first because March used to be considered the first month of the New Year.

Time Your Days by the Moon, Like the Romans Did

The Romans tied their calendar to the Moon’s phases. You can too. The Farmers’ Almanac Best Days Calendar shows the most favorable days each month for everything from planting to haircuts.

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The Old Calendar

There is a clue to all of this hiding in plain sight in our own calendar. Have you ever noticed that the last four months of the year have numbers in their names? September, October, November, and December come from the Latin words for seven, eight, nine, and ten. Those names do not make much sense when you consider that they are the ninth, tenth, eleventh, and twelfth months of the year. When you shift the beginning of the year from January back to March, though, those names suddenly fall into place.

Count it out for yourself. With March as month one, September lands as the seventh month, October the eighth, November the ninth, and December the tenth, exactly as their Latin roots promise. The names are a fossil of the older calendar, and they have outlasted the very system that made them sensible.

Julius Caesar and the Prophecy

As Emperor of Rome and spiritual head of the Empire, Julius Caesar would have naturally been expected to take part in the public festivities during this important day, despite the seer’s prophecy to “Beware the Ides of March.” Even though his wife, Calphurnia, prompted by troubled prophetic dreams of her own, also implored her husband to stay home, Caesar would not be swayed.

In fact, the historian Plutarch wrote that Caesar was defiant in the face of such warnings, boasting to the seer moments before his death that the Ides of March had come and her prophecy had not been fulfilled. To this, the seer replied, “Aye, Caesar; but not gone.”

When Caesar arrived at the Theater of Pompey, where the Roman Senate met, he was stabbed to death by a group of more than 60 conspirators led by the senators Brutus and Cassius, former friends turned enemies in the face of the Emperor’s unchecked ambition. “Et tu, Brute?” indeed. The date was March 15th, 44 BC, and it has carried the weight of that one afternoon ever since.

That the conspirators chose the Ides of March to carry out their plot was no coincidence. Not only was it a day when they could count on having access to the Emperor, but the religious meaning of the day weighed on their minds as well. By killing their leader on a day of sacrifice, the conspirators were sending a message that their leader’s blood was an offering to the gods, shed for the continued prosperity of their nation. For a fuller account of the day and its long afterlife, the historical record of the Ides of March traces how a routine calendar date became a byword for betrayal.

So, Should You Beware the Ides of March?

Here is the plain answer. The Ides of March is not an unlucky day in any measurable sense. It is a calendar marker that picked up a dark reputation because of one assassination more than two millennia ago, kept alive by a famous play. There is no folklore tying March 15th to bad weather, failed crops, or household misfortune the way other dates carry their own lore.

As March 15th approaches, you may still wonder if you should “Beware the Ides of March.” Unless you are a Roman Emperor, though, chances are your biggest worry is not whether you will become a sacrificial lamb, but simply whether March will exit like a lamb. Treat the day as the rest of us do, as a good excuse to brush up on a little history and watch the first full Moon of spring.

Main photo: “The Ides of March,” Artist Carl von Piloty 1894. Wikimedia Commons public domain.

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The Ides of March: Frequently Asked Questions

Jaime McLeod

Jaime McLeod is a longtime journalist who has written for a wide variety of newspapers, magazines, and websites, including MTV.com. She enjoys the outdoors, growing and eating organic food, and is interested in all aspects of natural wellness.

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