This week marks the day that Shakespearean scholars, practitioners of precognition, and ancient-Republic-abolishing Roman dictators fear and revere with equal abandon: The Ides of March. On March 15 in 44 B.C., conspirators stabbed Julius Caesar to death on the floor of the Roman Senate.

It was a historical event so profound that it moved such varied and accomplished luminaries as Plutarch, Thornton Wilder, and William Shakespeare (among countless others) to recount the tale of Caesar's demise. Appropriately, each of the above features the Ides of March quite prominently in his story.

And you thought the Ides were just another funky Elizabethan term that your English teacher used to make Shakespeare more insufferable. (Disclaimer: The Trivia Geek is a former English major who loves Shakespeare, but the Geek recognizes this as a minority position—Philistines, the lot of you!)

The Ides did arguably gain their contemporary notoriety due to The Bard, who included the famous line "Beware the Ides of March" in his play Julius Caesar, Act I, Scene 2, line 33. A soothsayer spoke the line, warning Caesar that tragedy awaited on this date and cluing the titular character in (albeit obliquely) to the murderous conspiracy to which the audience is openly privy. While Shakespeare may have used this dramatic device in his play in any circumstance—the man had a gift for plot construction—he also had some historical basis for the scene.

From the account of Nicolaus of Damascus, an Augustan-age (the reign of Caesar Augustus, the emperor who assumed control of Rome after the civil wars following Julius Caesar's death) historian, Caesar performed a traditional animal sacrifice to supplicate the gods before entering the Senate chamber on the Ides of March. The omens foretold by the sacrifice were reputedly ominous. In addition, Nicolaus suggests that Caesar's wife dreamt of his fate the night before his murder.

So, Shakespeare had some non-fiction backup for his soothsayer scene, even if he moved the event around in the play's timeline (it's what we call dramatic license, people). And by doing so, The Bard ensured that the Ides of March would become one of the most literarily notorious dates in history—even if most folks who observe the Ides don't know that the Romans recognized Ides in months besides March or that Ides were one of three categories of days observed in the ancient Roman calendar.

BESIDES THE IDES, WHAT WERE THE OTHER TWO SPECIFICALLY NAMED DAYS IN THE ROMAN CALENDAR?

What were the other two specifically named days in the ancient Roman calendars besides the literarily famous Ides, which earned notoriety thanks to Shakespeare's famous line "Beware the Ides of March" in his play Julius Caesar?

The Romans used three named days as reference points in their calendar: the Kalends, the Nones, and the Ides. What these days represented varied by the month; the lunar-based Roman calendar was a little obtuse. (Then again, I defy anyone to look at the modern Gregorian calendar and not say the same thing.)

The Kalends was always the first day of the month (and it's where the word calendar comes from). The Nones was the day of the first half moon, which fell either on the 5th or 7th day, depending on the month. The Ides was the day of the first full moon, which fell either on the 13th or 15th day, depending on the month.

In true Roman numeric fashion, these days served as base positions, with the current day counted backward from the Kalends, Nones, and Ides. Thus, just as IV would mean one before five (or four), adding numbers before the Kalends, Nones, or Ides signified a specific day of the month.

The term pridie meant the day before. Thus, if a Roman said pridie Ides Martius, it would mean the day before the Ides of March, or March 14.

The term ante diem could enumerate additional days before a named day, but the Romans counted inclusively. The phrase ante diem V Ides Martius would mean literally the fifth day before the Ides of March. However, instead of denoting March 10, it would mean March 11, because the five-day count included the Ides. Confused yet?

Moreover, after the Ides of a given month, the date would become a countdown to the following Kalends. So, the last day of March would be pridie Kalends Aprilis, or the day before the first of April.

As you might suspect, this convoluted complexity is what led to the adoption of a more conventional seven-day week in the third century A.D. However, informal references to the Kalends, Nones, and Ides survived for centuries, well into even Shakespeare's days, making for some lovely dramatic poetry—and some not-so-dated Geek Trivia.

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The Quibble of the Week

If you uncover a questionable fact or debatable aspect of this week's Geek Trivia, just post it in the discussion area of the article. Every week, yours truly will choose the best post from the assembled masses and discuss it in the next edition of Geek Trivia.

This week's quibble comes from the February 22 edition of Geek Trivia, "The math behind the myth." TechRepublic member Don Christner took a shot at my language skills.

"[You wrote] '. . . subsequently solves the mathematically insoluble.' Shouldn't that be unsolvable? Although, I suppose that a math problem can't dissolve in a solution."

Luckily, member LeeWin (and Dictionary.com) had my back.

"Insoluble: Difficult or impossible to solve or explain; insolvable: insoluble riddles."

Thanks for trying to sneak in the chemistry reference, but for once, the Geek is triumphant. Keep trying, and keep those quibbles coming!

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The Trivia Geek, also known as Jay Garmon, is a former advertising copywriter and Web developer who's duped TechRepublic into underwriting his affinity for movies, sci-fi, comic books, technology, and all things geekish or subcultural.