The month of vendémiaire is the first month of the republican Calendrier French.

It corresponded except for a few days (according to the year) at the period going of the September 22nd to the October 21st of the Gregorian Calendrier.

In addition, it roughly recovers the period during which the Sun crosses the sign of the Balance of the Zodiaque tropic.

It drew its name “ from the grape harvest which takes place of September in October ”, according to the terms of the report/ratio presented to the national Convention the 3 brumaire year II (October 24th 1793) by Fabre d' Églantine, in the name of the “charged commission of the clothes industry of the calendar”.

To note that this period corresponds well to the season of the grape harvest in the northern hemisphere. Although its originators wanted it universal, the republican calendar was very influenced by the French rural world.

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