The French Revolutionary Calendar

The logically-minded men of the French Revolution devised decimal systems of weights and measures and of currency, so why not a decimal calendar too? This project was entrusted to a group of mathematicians, scientists and a couple of poets by the Committee of Public Safety in late 1792, and next autumn the group’s proposals were implemented.

The new era was proclaimed to have begun on September 22^nd 1792, when France became a republic: the start of Year One of the new calendar. Much propaganda was made of the coincidence with the autumn equinox: all Frenchmen became equal at the same time as day and night were equal!

The year was to be made up of 12 months (even they couldn’t escape from this magic number!) each of 30 days. There were to be 5 extra days, “Festival days” outside the normal months, with a sixth added in leap years (the first of these being in Year III). To replace the weeks, each month was to have 3 decades of 10 days each; with a day divided into 100 minutes, and a minute into 100 seconds. There would thus be 100,000 seconds in a day, instead of 86,400 under the old system. Watchmakers were ordered to start making new watches for these new arrangements, and many of these survive.

The new days were prosaically named 1^st, 2^nd, etc, but the festival days were all given their own individual names, and a not-very-successful poet, Philippe Fabre d’Eglantine, was given the job of devising names for the new months. He decided to name them after climatic and agricultural themes (starting on September 22nd):- 

Vendemiaire, Brumaire, Frimaire, Niviose, Pluvoise, Ventose, Germinal, Floreal, Prairial, Messidor, Thermidor, Fructior.

    meaning, roughly:-

Vine-harvest, Foggy, Frosty, Snowy, Rainy, Windy, Budding, Flowers,

Meadow-grass, Reaping, Hot, Fruit.

Fabre’s names won official acceptance, but he did not enjoy his success for long. He was a close friend of the radical leader Danton, and when Danton’s group was purged by Robespierre in spring 1794, Fabre followed his leader to the guillotine.

The revolutionary calendar lasted a little longer. Napoleon Bonaparte staged a military coup in Brumaire 1799. In 1804 he crowned himself Emperor and sought a reconciliation with the Catholic Church, as a result of which Sunday was restored as a day of rest and the Gregorian calendar reinstated on January 1^st 1806. There have been no serious attempts to reform the calendar since then. Even suggestions to set a fixed date for Easter have invariably failed!