Hi everyone:
Familysearch.org has a fantastic collection of records such as the protestant registres between 1536-1863 of several departments and cities in France, Suisse and Germany.
For the Charente-Maritime, it has the following:
Charente-Maritime: La Flotte
Charente-Maritime: Le Douhet à Saintes
Charente-Maritime: St-Martin-de-Ré
See all in
https://familysearch.org/search/image/index#uri=https%3A%2F%... Good hunting!
Lucie