Petitbon was born in Pau in 1902,[1] the brother of writer and journalist Pierre-Henri [fr].
He then taught in lycées in Saint-Étienne and Clermont-Ferrand until joining the Alsatian Bank Society in 1928.
[2] A member of the resistance during the Nazi occupation, he was appointed prefect of Aube in 1944.
The following year he relocated to Algeria to become prefect of Constantine, a role he held until 1949.
He then became Inspector General of Administrative Affairs in French West Africa.