▁assumed ▁command ▁of ▁the ▁ 4 2 nd ▁Infantry ▁Division ▁( the ▁f amed ▁Rain bow ▁Division ) ▁at ▁Camp ▁Gr uber , ▁Oklahoma , ▁and ▁was ▁promoted ▁to ▁the ▁two - star ▁rank ▁of ▁major ▁general . ▁He ▁trained ▁the ▁ 4 2 nd ▁Division ▁in ▁the ▁United ▁States ▁for ▁ 1 6 ▁months ▁before ▁departure ▁for ▁over se as ▁service . ▁In ▁December ▁ 1 9 4 4 , ▁the ▁division ▁arrived ▁on ▁the ▁Western ▁Front ▁in ▁the ▁European ▁Theater ▁of ▁Oper ations . ▁The ▁ 4 2 nd ▁Division , ▁under ▁Collins , ▁played ▁a ▁major ▁role ▁in ▁stopping ▁the ▁last ▁German ▁drive ▁into ▁Western ▁Europe , ▁known ▁as ▁the ▁Battle ▁of ▁the ▁Bul ge . ▁The ▁division ▁then ▁went ▁on ▁to ▁take ▁part ▁in ▁the ▁Western ▁Al lied ▁invasion ▁of ▁Germany . ▁ ▁D ach au ▁liber ation ▁ ▁The ▁ 4 2 nd ▁Division ▁was ▁cred ited ▁with ▁the ▁liber ation ▁of ▁the ▁D ach au ▁concentration ▁camp . ▁As ▁commander ▁of ▁the ▁ 4 2 nd ▁Division , ▁Collins ▁had ▁def ied ▁convention ▁by ▁naming ▁Rab bi ▁( Capt ain ) ▁Eli ▁Boh nen ▁as ▁the ▁division ▁chap lain , ▁despite ▁not ▁having ▁a ▁large ▁number ▁of ▁Jews ▁in ▁the ▁division . ▁According ▁to ▁contemporary ▁accounts , ▁Collins ▁was ▁moved ▁by ▁the ▁pl ight ▁of ▁the ▁prisoners ▁he ▁saw ▁at ▁D ach au , ▁and ▁took ▁extraordinary ▁measures ▁to ▁ensure ▁they ▁immediately ▁received ▁housing , ▁food ▁and ▁medical ▁attention . ▁His ▁example ▁enabled ▁Boh nen ▁to ▁successfully