Republican Calendar

The republican calendar (or revolutionary calendar French ) was created during the French revolution of 1789.

The invention of this calendar was done gradually. As of the shortly after the Storming of the Bastille (July 14th 1789), the use had appeared to call 1789 “year I of (the era of) Freedom”; the months and days had remained the same ones, however. In year IV of the era of freedom, the September 22nd 1792, national Convention issued that “All the public acts from now on are dated as from year I from the Republic”. It is the September 20th 1793 which Charles Gilbert Rome, rapporteur of the work group named by the Committee of State education, present in front of Convention (the Committee itself having been entitled to a presentation six days before) what will become soon the republican calendar. After certain adjustments, it came into effect as from the shortly after the decree of the National Convention of the 14 vendémiaire year II (October 5th, 1793).

The nomenclature of the months and the days will continue to evolve/move in the months which followed. The decree was redesigned the 4 frimaire year II (November 24th 1793), which gave its final form to the calendar. This last decree abolishes the “vulgar era” for the civil uses and defines the September 22nd 1792 as being the first day of the “era of the French”. For the following years, the first day of the year would be that of the true equinox in Paris (what fell between the 22 and on September 24th according to the Gregorian calendar). The first year starts with year I, it thus does not have there a Année zero.

The 22 fructidor year XIII (September 9th 1805), Napoleon signed the Sénatus-consulte which abrogea the republican calendar and founded the return to the Gregorian Calendrier starting from the 1806.

The republican calendar was however re-used during the Commune of Paris in 1871 (Year LXXIX), and by Mussolini in 1922.

Structure

The purpose of the Revolution having made France a laic state, this calendar was to separate from the Gregorian Calendrier closely related to the Christianisme.

The organization of the new calendar was created by Gilbert Rome.

The year of the republican calendar was cut out in 12 30 days months each one (=360 days), plus 5 to 6 days (according to the years) additions at the end of the year so that it remains aligned with the Tropical year (~365 ¼ days). Each month was cut out in 3 10 days decades. The day is cut out according to the decimal system: “ of Midnight and midnight ”, it comprises ten hours cut out in 10 decomposable parts themselves in 10 parts, so on “ until the smallest commensurable portion of the duration”. This said, the decimal division of the day was abolished in 1795 (approximately year III).

The names of the months and the days were conceived by the poet Fabre d' Églantine with the assistance of André Thouin, gardener of the Botanical garden of the National Muséum of Natural history. Each name of month points out an aspect of the French climate (December, nivôse , snow) or important moments of the country life (September, vendémiaire , grape harvest). So this calendar that its originators wanted “universal”, was strongly related on its country of origin and the economic weight which the agricultural activities represented at the time.

The years sextiles

The calendar produced years sextiles (containing six days complementary) the years 3, 7, and 11 per one day addition to the end of the year, therefore a complementary sixth day. This day was called the " day of Révolution" , which marked the end of a Franciade and that one celebrated like a national festival.

One abolished the calendar in the An XIV. But the opinions differ on the future trend from the years sextiles if the calendar had remained into force. There are three assumptions:

According to some, the years sextiles would have continued every four years (thus years 15,19,23,27…).
According to others, the year sextile would have jumped year 15 at year 20, date from which every year sextiles would have fallen one year divisible by four (thus in 20,24,28…). This jump would have simplified conversions between calendars republican and Gregorian since there would have been agreement: for example the one day addition the February 29th 1812 is compensated a few months later by the addition of the day of the Revolution year 20. Imbalance thus persists only a few months instead of lasting more than one year.
According to a third opinion, the years sextiles would continue to vary in order to ensure that the 1 {{er}} vendémiaire falls each year on the autumnal equinox, as it was the case of the An I with the An XIV.

the correspondence of the dates below, is given as an indication. Indeed, they slightly vary from one year to another. A detailed correspondence is given to the articles An I with An XIV.