You've no doubt heard the phrase the Ides of March.  Do you remember from school what it means?  The Ides of March is the 15th.  And it was on this date in 44BC that Roman Emperor Julius Ceaser was murdered.

Each month of the year in the Roman calendar had an Ides.  It was a day near the middle of the month when the moon was full.

Today we only remember the Ides of March thanks to the infamous murder.

The term was the name of a 70s rock band, and a new George Clooney movie