His father was Jacques Monge, a merchant who came originally from Haute-Savoie in southeastern France. Gaspard's mother, whose maiden name was Jeanne Rousseaux, was a native of Burgundy and it was in the town of Beaune in Burgundy that Gaspard was brought up.
Kanyang ama ay Jacques Monge, isang merchant na dumating mula sa orihinal na Haute-Savoie sa dakong timog-silangan France. Gaspard ng ina, na ang apelyido sa pagkadalaga ay Jeanne Rousseaux, ay isang katutubo ng Burgundy at ito ay sa bayan ng Beaune sa Burgundy na Gaspard ay nagdala up.