France - Passport & Nationality - France Citizenship-Former Territories
There is a strong possibility you are French if one of your parents was born in a former overseas territory of France prior to Independence and you were born in France after that date and before January 1, 1994.
The situation may vary for parents of persons who were born in countries such as New Caledonia, the Wallis and Futuna Islands, French Polynesia, Mayotta, Algeria, Madagascar, the Camorra Archipelago, Affars and Issas, Vietnam, Cambodia and Laos, India, Tunisia, Morocco, Togo and Cameroon (former French territories).
As a general rule, if the parent was never issued official French citizenship papers during his/her lifetime, then there is a good chance that the French nationality petition of the child will fail. For more specific advice, you should speak to a professional.