Calendar History
Calendars and the idea of recording dates and time have challenged and inspired every culture throughout history. Early timekeepers relied upon the sun, moon, planets, and stars to record days, months, and years. Around 4000 B.C., the Egyptians first devised a 365 day calendar, based on observations of the moon's cycle. Thousands of years later, the Myans of Central America used the sun and the planet Venus to create a 365 day solar calendar. Over time, civilizations devised their own solar and lunar calendars, usually arranged with different numbers of days and months.

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In 46 B.C. Julius Caesar decided to correct the Roman Calendar. Over the years, it had become out of sync with nature and equinoxes were occurring too late for farmers. To remedy the problem, Caesar extended the year 46 B.C. to consist of 445 days, known as The Year of Confusion. He declared that leap year should fall once every four years in February, and he moved the start of the year from March 1 to January 1. In honor of Julius Caesar's calendar contributions, the month Quintilis was renamed July.

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By the time of Pope Gregory XIII, the Julian Calendar had become 11 minutes longer than the solar year and the extra time had accumulated to 10 extra days. In addition, for the past 36 years, leap year had been celebrated every three, not four years. On February 24, 1582, Pope Gregory XIII issued two changes to be made to the Julian calendar. First, October 5 through 14 were dropped from the 1582 calendar. Second, only the century years evenly divisible by 400 were to be leap years. The year 2000 was the first century leap year since 1600. The Gregorian calendar is so accurate there is only a 26.3 second difference between it and the solar year. Today, most everyone in the Western World uses the Gregorian calendar. However, there are still 40 different active calendars worldwide.