The Republican calendar was in use from 1793 through 1805, affecting civil registration and other government records in France and areas under French rule including including modern Belgium, Luxembourg, and parts of the Netherlands, Germany, Switzerland, and Italy. France returned to the Gregorian calendar on January 1, 1806, under Napoléon Bonaparte.
The French Republican calendar began with the autumn equinox. Years were counted from the founding of the French Republic on 22 September 1792.
- Each year had twelve months of thirty days each.
- Five days, called complementary days, were added to the end of the year to bring the total to 365.
- Every four years (beginning with year 3), an extra complementary day was added - to years 3, 7, 11, etc. During this period, the standard calendar had only two leap years (in 1796 and 1804).
Eager to overthrow the oppression of church and king, post-revolutionary France adopted descriptive calendar names reflecting reason, science and nature. Important! The twelve months of the French Republican calendar were based on the seasons of the year, and do not correspond to the standard months of January through December.
- Vendémiaire (vintage) - Sept. 22 - Oct. 21
- Brumaire (fog) - Oct. 22 - Nov. 20
- Frimaire (frost) - Nov. 21 - Dec. 20
- Nivôse (snowy) - Dec. 21 - Jan. 19
- Pluviôse (rainy) - Jan 20 - Feb. 18
- Ventôse (windy) - Feb. 19 - March 20
- Germinal (sprouting bud) - March 21 - April 19
- Floréal (flowery) - April 20 - May 19
- Prairial (meadow) - May 20 - June 18
- Messidor (harvest) - June 19 - July 18
- Thermidor (heat) - July 19 - Aug. 17
- Fructidor (fruit) - Aug. 18 - Sept. 16
Not only was each month in the French Republican Calendar named for natural themes, but each day of the year was also given a unique name. The "complementary days" (jours complémentaires ) at the end of the year were feast days, named in honor of Virtue, Genius, Labor, Opinion and Rewards. During leap year the additional day was called Revolution.
Dates were usually written out in French, or the country's local language, with the day, the month name and the number of the year of the French Republic (often designated as a Roman numeral).
Example: Le treizième jour du mois de Pluviôse lan sept de la République Française (the 13th of Pluviose in the seventh year of the French Republic).
Complementary feast days were recorded either by the name of the feast, or by the number of the day.
Because the days and dates for each year of the French Republican calendar were slightly different, it is easiest to use a chart or conversion tool to determine the standard calendar date for events which were recorded under the French Republican Calendar.
Calendar Conversion Tools

