Wikipedia
The Chouannerie was a royalist uprising in 12 of the western départements of France, particularly in the provinces of Brittany and Maine, against the French Revolution, the French First Republic, and even, with its headquarters in London rather than France, for a time, under the Empire. It played out in three phases and lasted from the spring of 1794 until 1800.
A first uprising attempt was carried out by the Association bretonne to defend the French monarchy and reinstate the specific laws and customs of Brittany that had been repealed in 1789. However, the massive uprising of an important part of the West and the transition to counter-revolution was mostly caused by the Civil Constitution of the Clergy and the levée en masse decided by the National Convention.
The first confrontations broke out in 1792 and evolved to a peasant revolt, then to guerrilla warfare and eventually to full-scale battles until the Republican victory in 1800. Shorter and less important peasant uprisings which took place in other départements such as in Aveyron and Lozère were also qualified as "chouanneries". A petite chouannerie broke out in 1815 during the Hundred Days and a final uprising ultimately took place during the Vendean War and Chouannerie of 1832.