Pope Gregory introduced the Gregorian calendar in 1582 and there was rioting
in the streets, The difference between the calendars was only 11 minutes and
16 seconds a year but had built up to 11 days over the centuries.
England (and the American colonies) changed calendars in 1752, and
Wednesday, September 2, 1752 was immediately followed by Thursday, September
14, 1752. This ange resulted in widespread riots and with the populace
demanding "Give us the eleven days back!"
Russia, did not follow suit until 1918, when January 31, 1918 was
immediately followed by February 14th. In fact, their calendar is not on the
Gregorian calendar but is in sync with it.
The French revolutionaries abandoned the Gregorian calendar in 1789 for
their own version but later went back to the Gregorian. The Grreks changed
in 1920 and there, too, was rioting. And finally a curiosity. The Greek
orthodox church in the USA clung to the Julian calendar until the 1980's and
this almost resulted in rioting in Chicago.
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