Year identification tables.

    Coin's pictures.

    Mints of France.

Origins of the calendar

    The French Revolutionary Calendar, or French Republican Calendar, was introduced in France by the Decree of 5 October 1793, AD. It was used from 24 November 1793 to 31 December 1805 (inclusive); on 1 January, 1806, it was abrogated by Napoleon. On September 22^nd, 1792 the French First Republic (République française) was proclaimed, so this date is considered to be the beginning of both the Republican Era and the French Republican Calendar. One day earlier, on September 21^st, the monarchy was abolished as the political system of France, and state power was passed to the Consul Napoleon Bonaparte from the French king Louis XVI.

    The French Revolutionary Calendar actually had a prototype, that is the so-called «Almanac of honest people», a book written by Pierre Sylvain Marechal and published in the beginning of 1788. Pierre Marechal (1750–1803) was a well-known French revolutionary-atheist at the end of the XVIII-th century. Charles-Gilbert Romme (1750–1795) was one of the active members of the French Revolution and author of the French Republican Calendar.

Structure of the calendar. Names of the months

    The year of the French Republican Calendar consisted of 365 or 366 days, divided into 12 months, the length of each month was exactly 30 days. 12 months were followed by 5 (in regular years) or 6 (in leap years) complementary days in a row. These extra days were called «the Sansculottides», after «sans-culottes» — the revolutionary-minded masses, — which literally meant «without knee-breeches». The point is that this kind of clothing had only been in use by the bourgeoisie and the noblemen, whereas the urban poor were unable to buy and wear them. Each month consisted of 3 ten-day periods. The government employees had only one day-off, i.e. the last (the 10-th) day of each ten-day period.

    A year of the French Revolutionary Calendar began in the autumn months, followed by the three months of winter, then came spring, and finally there were the three summer months. As you know, the months of the Gregorian calendar got their names from the names of the Roman emperors, roman digits and mythology. In the French Revolutionary Calendar these names were replaced by the new names, reflecting the phenomena of nature, weather and agricultural conditions of the climatic zone of France:

    As you can see, months within one season have identical endings, and due to this we can distinguish between the seasons only knowing the name of the month.

The Sansculottides and the leap years

    Each year of the French Revolutionary Calendar started on the autumnal equinox (September 22^nd). Thus, September 22, 1792, had become Vendémiaire the 1^st of the 1^st year of the French Republic (but the calendar itself was introduced, as stated above, only on November 24^th, 1793). Each day of the year had its own name as well.

    The names of extra days that were added after the last day of Fructidor are as follows:

    All these introductions were aimed at the dechristianization of the calendar. The Nativity of Christ, as well as the beginning of a new year on the 1^st of January were abolished. It was strictly prohibited to celebrate January 1^st as the beginning of a new year. On that day post office employees were authorized to open the citizens' envelopes and view the content of the letters, those that included season's greetings, were disposed of.

    The Sansculottides were introduced instead of the former Catholic feasts. Generally speaking, the Revolution itself, as well as the people's love of freedom and the hatred of the previous — feudal — state system had caused the introduction of the new calendar, which was free from religion.

    The French Revolutionary Calendar had one material shortcoming: there were no strict mathematical rules for the leap year calculation. Thus, the beginning of every year was determined by accurate astronomical observations and subsequent calculations. The New Year actually began at midnight on the day, on which, in accordance with the average Paris time, the autumnal equinox commenced.

    Hence the leap years could fall either after 4 or 5 years. For all of the time of the French revolutionary calendar, the leap years were: the 3^rd, the 7^th and the 11^th. Thus, the strict correspondence between the French Revolutionary Calendar and the Gregorian calendar is as follows:

    For convenience you can use the following two tables: one for direct year identification, and the other for reverse calculation (in case you need to know which year of the Revolutionary calendar falls on a given Gregorian year).

Mints

    18 different mints were striking coins for France during the period of time when the French Revolutionary Calendar was in effect. 16 of them were located in France, 1 in Switzerland (the city of Genèva) and 1 in Italy (the city of Turin). As a rule, the letter code (including one symbol or, in some cases, two symbols) was specified on a coin to the right of the date. The list of all the 18 mints is below. Their location can be found out on this piece of a Yandex-map (click to show/hide).

Update @January 4-th, 2012: according to Peter, administrator of the forum “World of coins”,

„France is a well-known case of centrally made dies. All dies were made in Paris and shipped out to the provincial mints. These added the mint mark and, if necessary, the mark of the director and chief engraver of the mint. Another example is the UK, where the mint in London outsourced striking some colonial coins to the (private) Birmingham mint. Again, the dies were made in London, the mint marks added locally (or the unwanted mint mark filled in, as the case may be)“.

    Numbering in the Yandex-map picture above is just the same as in the table below:

Pictures of a coin minted during the French Revolutionary calendar

20 francs («the Gold Napoleon», from French «Napoléon d'or»); reverse; mint: «A» (Paris); year of French Revolutionary calendar: 12, year of the Gregorian calendar: 1803

Ruler's title: «Bonaparte, Premier Consul» (Bonaparte, the First Consul of the French Republic); obverse

    Image source: Russian treasurehunting forum samara-clad.ru, user Баюн