Born the eleventh child in a poor family from Montpellier, Lepic joined a dragoon regiment at age 16 and benefitted from the outburst of the French Revolution, which facilitated his promotion to squadron commander (March 1793). He was at first involved in fighting against the Vendéean insurrection, before moving to the 'Army of Italy' in 1796, where he was remarked for gallantry and was wounded several times. Lepic remained in Italy until the end of 1805, when he was named "colonel major" of the Grenadiers à Cheval de la Garde Impériale regiment of the newly created Imperial Guard, which he would command for the rest of his military career.