After they left Grenada they relocated to St. Lucia. Would anyone know if there is a ship manifest that may record when they left France
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I did and they suggested I go to the community to ask
You could look at the FIBIS Fibiwiki page West Indies to see whether there are any sources which could be helpful to you, although it is mainly about the British In the West Indies.
You could also look at the FIBIS Fibiwiki page French. This is mainly about the French in India, but as St Lucia was at one time a French colony, there may be something in the online records from Archives Nationales d'Outre-Mer (ANOM)
Perhaps you could consider a researcher in France.
Thank you, I tried but limited to India.
I used a French researcher however she focused on Grenada