Ides of March

In the Roman Calendar, the Ides of March fell on the 15th day of the Roman month of Martius. The word ides comes from a Latin word that means to divide. The ides is simply the middle of the month.
Although the Roman calendar was eventually displaced by the modern days of the week around the third century, the Ides continued to be used for centuries afterwards. When Shakespeare wrote the famous line "Beware the Ides of March!" in Julius Caesar, he did so in the reasonable assumption that his audience would know the date of Caesar's death and so have a good idea of what the Ides were. The date is famous because Julius Caesar was assassinated on the Ides of March, 44BC. Because of Shakespeare’s play Julius Caesar and its line “Beware the Ides of March”, the Ides of March has a sense of doom.

The Roman calendar organized its months around three days, each of which served as a reference point for counting the other days:

• Kalends (1st day of the month)
• Nones (the 7th day in March, May, July, and October; the 5th in the other months)
• Ides (the 15th day in March, May, July, and October; the 13th in the other months)
  

The remaining, unnamed days of the month were identified by counting backwards from the Kalends, Nones, or the Ides. For example, March 3 would be V Nones—5 days before the Nones (the Roman method of counting days was inclusive; in other words, the Nones would be counted as one of the 5 days).