▁and ▁fought ▁its ▁major ▁actions ▁in ▁the ▁Saint - M ih iel ▁and ▁Me use – Arg onne ▁Off ens ives ▁in ▁late ▁ 1 9 1 8 . ▁Organ ized ▁into ▁two ▁field ▁arm ies ▁( a ▁third ▁was ▁forming ▁as ▁the ▁war ▁ended ), ▁it ▁had ▁a ▁total ▁strength ▁of ▁about ▁two ▁million ▁men ▁in ▁Europe ▁by ▁the ▁time ▁of ▁the ▁Arm ist ice . ▁Pl anned ▁to ▁eventually ▁consist ▁of ▁nine ▁corps , ▁a ▁total ▁of ▁five ▁A EF ▁corps ▁and ▁two ▁un ass igned ▁divisions ▁were ▁in ▁the ▁field ▁by ▁September ▁ 1 9 1 8 . ▁It ▁was ▁subsequently ▁involved ▁in ▁the ▁Occ up ation ▁of ▁the ▁Rh in eland . ▁ ▁First ▁Army ▁ ▁The ▁First ▁Army ▁was ▁officially ▁organized ▁and ▁activ ated ▁by ▁General ▁John ▁J . ▁Pers hing ▁on ▁ 4 ▁July ▁ 1 9 1 8 , ▁although ▁it ▁was ▁techn ically ▁formed ▁when ▁the ▁United ▁States ▁entered ▁the ▁World ▁War ▁in ▁ 1 9 1 7 . ▁It ▁served ▁in ▁the ▁Saint - M ih iel ▁off ensive , ▁Lor raine ▁off ensive , ▁Champ agne ▁off ensive , ▁and ▁the ▁Me use – Arg onne ▁Off ensive . ▁It ▁was ▁finally ▁dem obil ized ▁and ▁moved ▁back ▁to ▁the ▁United ▁States ▁on ▁ 3 0 ▁April ▁ 1 9 1 9 . ▁ ▁Second ▁Army ▁ ▁The ▁Second ▁Army ▁was ▁activ ated ▁on ▁ 9 ▁September ▁and ▁was ▁organized ▁by ▁Colonel ▁Stuart ▁He int zel man . ▁On ▁ 1 2 ▁October