In 1737, the duke of Lorraine, François Étienne, signed away his duchy to France, in exchange for French support for his marriage to Maria Theresa of Austria.
As a result, Françoise de Graffigny left Lorraine for Paris, and her intermittent correspondence with Devaux became an almost daily record of both their lives, until her death in 1758.
She used her influence for his benefit, getting him a post as a revenue collector in 1741, helping secure his election to the Académie de Nancy in 1752, obtaining for him a sinecure as reader to King Stanislas, and thanks to her success as a playwright, persuading the actors to produce his play, which had been retitled Les Engagements indiscrets.
[citation needed] From 1758 until his own death in 1796, Devaux lived an idle life in Lunéville, frequenting the houses of noble families of Lorraine, attending sessions of the Académie de Nancy, and writing occasional verse.
The manuscripts of many of his poems are now in the Bibliothèque municipale de Nancy, and a generous selection of them, along with his play and his discourse, were edited and published by Angela Consiglio in 1977.
[3] He was eventually coaxed into a sexual relationship by his neighbor, Barbe Lemire, and he occasionally slept with an actress friend, Clairon Lebrun.