It’s February 29th, a date that comes only once every four years and just who can we thank for that? According to a Wired article today, none other than Roman Emperor Julius Caesar.

Caesar was reforming a calendar based on 364 days, with an occasional extra leap month. But the Roman religious officials in charge of minding the calendar had been asleep at the switch, chronologically speaking. Caesar consulted with Egypt’s top astronomers, who told him the year was 365¼ days long. While he was making the fix, Julius also decided to give his name to the month of July.
Although Caesar decreed the new calendar in 46 B.C., that year had 15 months to make up for the accumulated discrepancy. The first add-a-day leap year was 45 B.C.

Via / Wired