Human World

Ides of March: Why should you beware?

Close-up of a calendar with the text March 15 in focus and a red pushpin sticking into it.
The Ides of March fall on the 15th. Image via Encyclopedia Britannica.

What are the Ides of March?

If you’ve heard of the Ides of March, you probably know you’re supposed to beware them. Why? In ancient Rome, the Ides of March were equivalent to our March 15. In the Roman calendar, this date corresponded to several religious observances. The Romans considered the Ides of March a deadline for settling debts. But – in our modern world – if you’ve heard of the Ides of March, it’s probably thanks to William Shakespeare. In his play Julius Caesar, a soothsayer attracts Caesar’s attention and tells him:

Beware the ides of March.

Caesar demands:

What man is that? Set him before me, let me see his face.

When the soothsayer repeats his warning, Caesar dismisses him, saying:

He is a dreamer; let us leave him. Pass.

Then, two acts later, Caesar is assassinated on the steps of the Senate.

In the play – and in reality – Julius Caesar was indeed assassinated on the Ides of March, or March 15, in the year 44 BCE. So, while Julius Caesar should have been wary about the Ides of March, the rest of us don’t need to worry.

A lot of horrified Romans watch someone pointing at Julius Caesar.
The soothsayer tells Caesar to beware the Ides of March … but Caesar doesn’t listen. Image via

Marking the months

In the ancient Roman calendar, each month had an Ides. For the months of March, May, July, and October, the Ides fell on the 15th day. In every other month, the Ides fell on the 13th day.

The word Ides derives from a Latin word that means to divide. In the beginning, the Ides marked the full moons, but because calendar months and lunar months were different lengths, they quickly got out of step.

The Romans also had a name for the first day of every month: the Kalends. Our word calendar derives from Kalends.

In fact, our modern calendar is very much like the one that Julius Caesar enacted the year before his death. It had 365 days and 12 months each year. It even took into account the fact that Earth’s orbit around the sun isn’t a whole number of days, by adding a leap day every few years.

Ides of March: A sign just saying 'Beware the Ides of March'.
Beware! Image via veraukoion.

Bottom line: The Ides of March corresponded to March 15 in ancient Rome. We remember them thanks to William Shakespeare’s play “Julius Caesar.”

March 12, 2022
Human World

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