Julian Calendar History. By the 40s bce the roman civic calendar was three months ahead of the solar calendar. In 45 bce, julius caesar introduced a significant reform known as the julian calendar.

He added an extra day to february every four years to keep it on schedule with the seasons. Discover the fascinating history behind the missing 11 days of october 1582 and how the gregorian calendar was introduced to correct the inaccuracies of the julian calendar.