Date of first record epends on location.
Civil records start around 1793 (early years are sometimes a bit dodgy). Before that you have parish records.
Catholic church records, for the parishes I'm interested in the Vendee department, vary in starting dates - 1650, 1688, occasionally going back to the late 1500s. (often there will be damage/gaps, of course). There is one for which the early records seem to have been lost leaving that line hanging around in the mid-1700s.
Protestant records they also have online - earliest 1636. Depending on the location again - there may be some areas for which you go back before 1600 (but probably not far before).
On the side of Reine Warnier, an important document to locate would be the marriage to Louis Alfred Cuquemelle.
I did find a possible birth - Reine Warnier, 21 April 1841 - in the Paris documents, but this is part of the "reconstructed" records so no further info on the index than that (there should be more info but not online, I think).