Wikipedia
In the French Republican calendar, the franciade was the period of four years at the end of which it was necessary to add a day to the calendar year to keep it aligned with the solar year (c. 365¼ days).
The franciade was defined in 1793 in article 10 of the Décret de la Convention nationale portant sur la création du calendrier républicain, as follows:
The period of 4 years, at the end of which this addition of one day is usually necessary, is named the franciade, in memory of the revolution which, after 4 years of toils, led France to its Republican government.
La période de quatre ans, au bout de laquelle cette addition d'un jour est ordinairement nécessaire, est appelée la franciade, en mémoire de la révolution qui, après quatre ans d'efforts, a conduit la France au gouvernement républicain.
The day that was thus added at the end of the jours complémentaires was called the jour de la révolution ( Revolution Day).
Franciade was also the name given to Saint-Denis from 1793 to 1800.
La Franciade (known in English as the Franciad) is an unfinished epic poem written in decasyllabic verse by Pierre de Ronsard. Ronsard began writing the poem in the 1540s for Henri II, but it was only in 1572 that the poet published, now for Charles IX, the first four books of a planned twenty-four. Various reasons have been given to explain why the poem was never finished. Obviously, the death of his dedicatee Charles IX meant that Ronsard would have to have made certain changes. Another factor might have been the verse form: Ronsard wrote in decasyllables, not alexandrines. Other reasons, too, have been put forward. More recently, it has been stated that "[any] attempt to pin down why the Franciade was left unfinished, while potentially interesting, probably futile" and that "we must read it despite [the fact it is unfinished], not as a fragment of what might have been, but as a text in its own right"