[4][5] His older brother, La Salle Proisy, also served in the Navy.
[6] Proisy joined the Navy as a Garde-Marine on 26 November 1745.
[4] On 19 March 1763, he was made a Knight in the Order of Saint Louis.
[4] In 1765, he commanded the fluyt Forte,[7][8] carrying wook from Pyrenees.
[6] In 1778, Proisy captained the 64-gun Actionnaire, part of the White squadron under Orvilliers.