Hi Steve, I have some information on a Leudy Mustain who was the daughter of a Thomas Mustain b. 30 September 1713 d. 21 November 1791. This Thomas was living in England with his Grandfather Francis until his grandfather's death in 1722. He attended school there where he was educated as a clerk. I have a list of books that he checked out from the University libary while he was a student. I am trying to read a few of these myself at the present time.
Young Thomas appears to have been a distant cousin of Admiral d'Estaing who commanded the French Fleet who aided the Americans against the British during the Revolution. They both shared the same great grandparents. My records show that although the family of Thomas Mustain were living in England the family was actually French and a fair number of them already had extensive land holdings in Jamaica, Mauritius, and VA during the 1600s. Also, The family owned their own shipping concerns and conducted trade in Mascarene Sugar Ivory and Tortoise Shell.
There were several generations of Leudy/Leudas but tracing it back it seems that Leuda was a placename in France near where the family originated (near the Pyrenees between France and Spain). The family split along religious lines during the 1500s with some remaining Huguenot while others converted to Catholicism. The family of our Thomas fled from Fougere France to England upon the Revocation of the Edict of Nantes. The original name of the family was d'Estaing but owing to emigration the name was morphed to include the following variants(LesTaine, m'Estaing, l'Estaing, Moustine, Eastain, Mission, Moustien and oddly enough Mission).