Kammala jumla mai zuwa: Ya tashi zuwa Faransa a ranar 4 ga Fabrairu, 1918, a matsayin memba na Kamfanin 119 na Battalion na Farko na Farko, Marine Corps na Amurka, ya isa Brest a ranar 26 ga Fabrairu. Daga nan sai kamfaninsa ya shiga horo a Châtillon-sur-Cher, yayin da Overton ya tafi makarantar horar da jami'ai a Gondremont, Faransa, kusa da Bezange-la-Grande. Ya kammala karatunsa a saman aji a ranar 31 ga Mayu, 1918, kuma an aika shi a ranar 1 ga Yuni don kallo tare da Forty Second Regiment na Chasseurs na Faransa da ke zaune a tsaunukan Vosges. An fara shi a matsayin memba na girmamawa na Chasseurs na Faransa kuma ya kasance tare da rundunar daga Yuni 1 <unk> 13. Lokacin da Marines suka shiga cikin Chateau-Thierry a farkon Yuni, ya nemi a canja shi daga kamfaninsa wanda har yanzu yana cikin horarwa zuwa layin gaba, kuma a ranar 16 ga Yuni ya isa sansanin soja a tsakiyar yakin Belleau Wood, wanda ya fara ranar 1 ga Yuni kuma zai ci gaba har zuwa Yuni 26. A can, an sanya Overton a matsayin laftanan na biyu a cikin Kamfanin na 18, 6th Regiment, Marines na Amurka, wani ɓangare na Brigade na 4 da Division na 2. Ya yi aiki a Belleau Wood har zuwa Yuli 9. A ranar 2 ga Yuli an daukaka shi zuwa laftanan farko, amma ba zai koyi hakan ba har sai mutuwarsa. Daga Yuli 9<unk>16 ya yi aiki a Nanteuil-sur-Marne. A ranar 16 ga Yuli, an tura rundunarsa tare da rundunar ta 5 zuwa gaban Faransa kusa da Soissons don shiga cikin
Yaƙin Marne na biyu. Rukunin ya kasance wani ɓangare na Marshal Ferdinand Foch's allied offensive a kan Soissons salient ya fara Yuli 18, 1918, sashinsa a ƙarƙashin Janar Charles Mangin na Faransa.