Rubuta ci gaba don wannan sakin layi - De Borre ya fara aikin soja a cikin sojojin Faransa na sarauta a matsayin mai sa kai. Ya yi aiki a matsayin jami'in sojan doki a cikin kamfen da yawa a lokacin Yaƙin Nasara na Austriya. A shekara ta 1745 ya ji rauni sosai. A shekara ta 1757 ya kafa wani rukuni daga garinsa na Liège a yanzu Belgium amma a bayyane yake bai ga wani aiki ba a cikin Yakin Shekaru Bakwai. Lokacin da ya isa Amurka a 1776, na biyu Continental Congress
ya ba shi mukamin brigadier janar. George Washington ya sanya de Borre ya jagoranci Brigade na 2 na Maryland a cikin sashen John Sullivan. Ya jagoranci sojojinsa a Staten Island da Brandywine. A wannan yaƙin na ƙarshe ya nuna bai iya kula da sojojinsa a cikin aiki ba. An yi barazanar da kotun soja, ya yi murabus kuma ya bar Amurka a 1779. An daukaka shi zuwa brigadier janar a cikin sojojin Faransa a 1780 amma ba shi da ikon yin aiki a jiki.