Change In October 1582 & September 1752 Calendar

In 1582, the Catholic Church decided to fine-tune the calendar they used since they felt Easter didn’t fall anymore on what they thought was the correct day every year. And thus the Gregorian Calendar was invented to replace the Julian Calendar. When that was done, they had to get rid of 10 days to re-adjust the yearly cycle. So for the Church, the last day of the Julian calendar was Thursday October 4, 1582, which was followed the next morning by the first day of the Gregorian calendar, Friday October 15, 1582.

But not everyone was Catholic, or followed these Catholic decisions in the matter of calendaring. Catholic countries switched from the Julian to the Gregorian system relatively quickly (Spain, Italy, Poland, etc), but others followed much later (Russia, 1917; Greece, 1923). The United Kingdom and its colonies (like Canada and the American Colonies) did the switchover in 1752, September 2, 1752 was followed by Thursday September 14, 1752 for these people. and got rid of 10 days when switching calendar: Wednesday

        October 1582 In                                        September 1752 In
    
     Gregorian Calendar                                       Julian Calendar

Su Mo Tu We Th Fr Sa            Su Mo Tu We Th Fr Sa

    1  2  3  4 15 16                   1  2 14 15 16

17 18 19 20 21 22 23            17 18 19 20 21 22 23

24 25 26 27 28 29 30            24 25 26 27 28 29 30

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