The Julian and Gregorian Calendars

  The Julian calendar was introduced by the Roman Emperor, Julius Caesar, in 46 BC in the 708th year of the founding of Rome with each year beginning on the 1st Ianuarius. The Normans generally used 25th December as the start of the year.  However from the late twelfth century up to 1752 AD (CE), the first day of the legal year was chosen as March 25th (Lady Day) and the last day March 24th.  So 24th March 1750 was followed by 25th March 1751.

  In 1582 Pope Gregory modified the leap year arrangement slightly as the average Julian year was 11 minutes 14 seconds too long but it was 1752 before Protestant England adopted the new calendar. The year was changed to begin on 1st January after December 1751 and an adjustment of days was needed so 11 days were removed and 2nd September 1752 was immediately followed by 14th September.

Julian Date:   Gregorian Date:    


Weekday:    Calendar in use in UK and USA

Julian Day Number(JD):

Julian day numbers used in astronomy began at noon on Monday, 1st January of year 4713 B.C. in the Julian calendar.
Changeover - Italy, Spain and her colonies, between Thurs. 4th & Fri. 15th October 1582.
England and her colonies, between Wed. 2nd & Thurs. 14th September 1752.
Russia, between Wed. 31st January & Thurs. 14th February 1918.
The current Julian Period began at 12 noon on 1st January 4713 BCE/BC
and will end at 12 noon on 1st January 3268 CE/AD.
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