Rubuta ci gaba don wannan sakin layi - Bayan karatun a Kwalejin Soja ta Sorèze (1793 <unk> 1798), ya shiga rukunin 1st Hussards a matsayin mai sa kai a ranar 3 ga Satumba 1799. Ya yi aiki a karkashin Janar Jean-Mathieu Seras, wanda ya ba shi mukamin sarjan a ranar 1 ga Disamba, 1799. A cikin wannan watan, a ranar 31 ga Disamba, 1799, an daukaka shi zuwa mukamin laftanan na biyu don girmama ƙarfin zuciyarsa. Ya yi yaƙi da sojojin Italiya kuma ya shiga cikin yakin Marengo
da Siege na Genoa, a lokacin da mahaifinsa, Janar Jean-Antoine Marbot ya mutu.