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Great Britain began using the current calendar in 1752.
1752
2009
1752
Great Britain and her colonies adopted the Gregorian calendar on September 14, 1752. The previous day was September 2.
Because in the Chinese Calendar, which is the Lunar Calendar, it is the New Year. The Lunar Calendar and Solar Calendar is different.
The Gregorian calendar
Generally speaking, a calendar year begins on the New Year's Day of the given calendar system and ends on the day before the following New Year's Day. By convention, a calendar year consists of a natural number of days.
Under the Gregorian calendar New Year's Day is January 1st.
either solar or lunar calendar
Chinese New Year is based on the Lunar calendar, in which the days of a month are different from the Solar Calendar that we normally use.
Nowadays, Ukraine uses the gregorian calendar. However, they used to use their own calendar. On 14 January, what Ukrainians call old new year today was the old ukrainian calendar's new year.