Every four years, our calendars reveal an anomaly - February gets an additional day, known as Leap Day. What is the purpose of this day and why do we have it?
Adding an extra day to the calendar can be traced back to ancient civilizations. Already by the third century BCE, the Egyptian calendar included a leap year in order to synchronize their solar calendar with the seasons. The Julian calendar, which began in 45 BCE, drew on this idea and included an extra day in February every four years.
However, the Julian calendar slightly miscalculated the solar year at 365.25 days instead of the actual 365.2422 days. The result was that by the sixteenth century the calendar was significantly off. Pope Gregory XIII introduced the Gregorian calendar to fix the problem. While it kept a leap day every four years, it eliminated it during the centurial years not divisible by 400.
Even though the primary purpose of Leap Day is to maintain temporal accuracy in our calendar system, it has become associated with various traditions and rituals. According to an Irish legend, Saint Brigid of Kildare convinced Saint Patrick to allow women to propose to men on leap year and this tradition has spread across Europe and beyond. Parallel traditions developed that a man should pay a penalty should he refuse the proposal. Depending on the region the penalty might be money, a silk dress, twelve pairs of gloves, or enough fabric to make a skirt. Other regions see leap year as unlucky. Greek traditions suggest a marriage made during a leap year will end in divorce and in Germany “Schaltjahr gleich Kaltjahr,” meaning "leap year will be a cold year."
People born on February 29 have the rarest of birthdays and are known as leaplings or leapers. They often endure jokes about having very few birthdays, but leaplings are usually very proud of their birthdays. In fact, since 1988, Anthony, New Mexico has a multi-day festival to celebrate those who have birthdays on February 29, with people traveling from all over the world to join the party.
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