Printer to the king of Prussia - the Principality of Neuchâtel was at that point Prussian - a Freemason and a Calvinist, Fauche-Borel welcomed the French Revolution.

However, the influx of French émigrés radically altered his opinions and he became affiliated with the counter-revolution.

In 1795, Montgaillard made him responsible for making contact with Jean-Charles Pichegru and Louis Joseph, Prince of Condé.

He wrote some insignificant reports, but secretly printed the proclamations of Louis XVIII to send to Paris.

A machination by Fouché led him to believe that a royalist committee was bringing together high-ranking personages in Paris.