The birth date for Jean Grasset Latour is uncertain. Duhamel notes that the acte de décès for Jean Grasset Latour gives his birth place as Bergerac in 1761. This document also reveals the names of his parents: Pierre Grasset and Marie Bontemps (Dontemne is most likely a contempory transcription error by the mairie in Perpignan). However, searching Begerac parish records from 1754 to 1771, Duhamel found no baptismal record for Jean Grasset-Latour, nor for his elder brother Pierre Grasset Latour who was born about 1758. Duhamel assumes that these two eldest children of Pierre Grasset and Marie Bontemps may have been born au Désert, i.e., under the Protestant faith, as their parents were married outside the Catholic Church. Protestant Church records for this period are extremely hard to find.

During research at the Vincennes Military Archives in Paris, France, Duhamel found additional background information on Capitaine Jean Grasset Latour. One document erroneously gives Jean Grasset Latour a Bergerac birth date of 6 March 1762. Although the Bergerac parish birth/baptismal records provide no evidence of this birth date, the records do have a baptism on 14 October 1762 for Jean's three day-old sister Marguerite Grasset-Latour.

The military document uncovered by Duhamel'sVincennes Military Archives indicates that Jean Grasset Latour was a poélier (stove maker) before joining the military and that his father was a cordier (rope maker). This same document notes Jean had served in the Guard since the beginning of the French Revolution and with good conduct. He also had a good physical consitution, disposition and manners, but few aptitudes. His was a capitaine, non-brévété (non-commissioned) in the Fifth Battalion of Dordogne.

Duhamel also was unable to find the acte de mariage for Jean Grasset Latour and Marie Bertrand either in Dordogne (Bergerac, La Force, and Sigoules), nor in La Rochelle between the dates of 1793 and 1797. She concludes that the marriage could have taken place before this four-year period or in some other town, given that Jean Grasset Latour was in the military.

The acte de décès (death record) for Jean Grasset Latour from Perpignan, Pyrénées Orientales, France states that his birth was in Bergerac in 1761, based on his age at death of 50 years. The acte de decès also reveals the names of Jean's parents: Pierre Grasset and Marie Bontemps ("Dontemne" is most likely a contemporary transcription error).