Rubuta ci gaba ga wannan sakin layi - A shekara ta 1789, Lefebvre ya kasance wani jami'in soja a cikin Gardes Françaises. Bayan rushewa, ya shiga cikin Tsaron Kasa, inda ya sami raunuka yana kare dangin sarauta daga fushin jama'a, bayan haka ya shiga juyin juya hali. An daukaka shi zuwa brigadier janar a 1793, ya shiga cikin yakin Fleurus (24 ga Yuni 1794). Bayan mutuwar Janar Louis Lazare Hoche ya jagoranci rundunar sojojin Sambre-et-Meuse (Satumba 1797). Daga nan sai ya yi umurni da jagorancin Sojojin Danube karkashin Jourdan a watan Maris na 1799, kodayake a makon farko na yakin ya kasance ba shi da lafiya tare da ringworm kuma Dominique Vandamme ya maye gurbinsa na ɗan lokaci. Daga baya ya ji rauni a yakin Ostrach.
inda masu tsaron gaba suka dauki nauyin yakin farko. A watan Nuwamba 1799, Lefebvre ya umurci sojojin Paris kuma ya yarda ya goyi bayan Napoleon Bonaparte a cikin "coup d'état". A shekara ta 1800, Bonaparte ya nada shi sanata.