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Historical European new year dates

During the Roman Republic and the Roman Empire, years began on the date on which each consul first entered the office. This was probably May 1 before 222 BC, March 15 from 222 BC to 154 BC, and January 1 from 153 BC. In 45 BC, when Julius Caesar 's new Julian calendar took effect, the Senate fixed January 1 as the first day of the year. At that time, this was the date on which those who were to hold civil office assumed their official position, and it was also the traditional annual date for the convening of the Roman Senate. This civil new year remained in effect throughout the Roman Empire, east and west, during its lifetime and well after, wherever the Julian calendar continued in use.

In the Middle Ages in Europe a number of significant feast days in the ecclesiastical calendar of the Roman Catholic Church came to be used as the beginning of the Julian year:

Over the centuries, countries changed between styles until the Modern Style (January 1) prevailed. For example,

A more unusual case is France, which observed the Northern autumn equinox day (usually September 22) as "New Year's Day" in the French Republican Calendar, which was in use from 1793 to 1805. This was primidi Vendémiaire, the first day of the first month.