Son of Pierre Feronce and Marguerite Marin. Privy Councillor (1761-) to Karl I of Brunswick, and Finance Minister (1773-) to Karl Wilhelm Ferdinand. He was admitted a Fellow of the Royal Society (UK) on June 28, 1764, the day after Boswell's first meeting with him.
A biography of the painter Benjamin Constant tells us that "Minister Féronce, widely read and possessed of an acid wit, took the young man [Constant] under his wing, while quietly despairing at Constant’s inability to organize his life better."1
- 1. Wood, D. (1993). Benjamin Constant: A Biography. Routledge. p. 108.
Boswell waited on Feronce at Brunswick on June 27, 1764, delivering a letter from Count Bentinck whom he had met a few times during his stay in Holland. He found Feronce "a man of polite science, lively and easy." Boswell seems to have made a good impression on Feronce as well, and later on that day, he was introduced to "all the Grands [...] and to the Dames d'honneur" at the court, before meeting the Duke and Duchess of Brunswick themselves.
When Boswell returned to Brunswick on August 7, Feronce seems again to have been one of the first people he visited (on August 8), and he was also one of the persons in that city who agreed to keep up a correspondence with Boswell after he left.