In a book "Apellidos de Tamaulipas, Nuevo Leon y Texas" (author?) someone quoted for me that our Miguel Chauvain (now Chavana) was born 1719 in Limoursin/Limoges, France. He came in 1735 with the French army for the invasion of Lousiana, lived in New Orleans, deserted and somehow arrived in Lampazos, NL where he married Ma. Catarina de Leon. Miguel's father was Diego Chauvain and his mother Juana Trobada (or Novada).
I am curious about how you were able to trace your Chavana ancestry that far back, what sources did you use? Since I am not a genealogy researcher, my database consists primarily of what I have integrated by exchanging information with other people.