91st Division ( United States ) The 91st Infantry Division ( variously nicknamed as the " Pine Tree Division " or " Wild West Division " ) was a unit of the United States Army that fought in World War I and World War II . From 1946 until 2008 , it was a part of the U . S . Army Reserve . It was briefly inactivated from 2008 until 2010 when it was elevated back to a division size element as the 91st Training Division ( Operations ) . History . World War I and after . Constituted on 5 August 1917 at Camp Lewis , Washington , near Tacoma , the division soon thereafter departed for England in the summer of 1918 . In September 1918 , the division ' s first operation was in the St . Mihiel Offensive in France . Serving under the U . S . Army ' s V Corps , the division fought in the Meuse - Argonne Offensive and successfully helped to destroy the German First Guard Division and continued to smash through three successive enemy lines . Twelve days before the end of World War I , the division , as part of the VII Corps , helped drive the Germans east across the Escaut River . The division was awarded separate campaign streamers for its active role in the Lorraine , Meuse - Argonne and Ypres - Lys campaigns . In 1919 , the 91st was inactivated at the Presidio of San Francisco . After being reconstituted in 1921 as part of the Organized Reserves , the division then served as an administrative control center for the next 21 years . World War II . As the first battles of World War II involving the United States were being fought in 1942 , the division was reactivated at Camp White , Oregon . After initial training at Camp White , the division participation in the Oregon Maneuver combat exercise in the fall of 1943 . Then , the division departed for the European Continent . There , the 361st Regimental Combat Team was detached to participate in the battles for Rome and the Arno River . It became the first Fifth Army unit to reach the river . In September 1944 , the division crossed the Sieve River , outflanked the famous Gothic Line , and captured the Futa Pass . For its part in combat , the division was awarded the North Apennines , Po Valley and Rome - Arno campaign streamers . The division was inactivated at Camp Rucker , Alabama , in December 1945 . WWII Statistics - . Awards : MH - 2 ; DSC - 2 ; DSM - 1 ; SS - 528 ; LM - 33 ; SM - 43 ; BSM - 4 , 152 . Theater : Mediterranean Casualties : 8 , 744 ( casualties are number of killed , wounded in action , captured , and missing ) Days of Combat : 271 Campaign ( s ) : Rome - Arno ( 22 Jan 44 - 9 Sep 44 ) North Apennines ( 10 Sep 44 - 4 April 45 ) Po Valley ( 5 Apr 45 - 8 May 45 ) Army Reserve . In December 1946 , the 91st was reactivated at the Presidio of San Francisco as part of the U . S . Army Reserve . In 1959 , the division was reorganized and redesignated as the 91st Division ( Training ) . In 1993 , the division was again reorganized and redesignated as the 91st Division ( Exercise ) and again in 1999 as the 91st Division ( Training Support ) . Its previous headquarters were at Parks Reserve Forces Training Area ( PRFTA ) , Dublin , California . In its 2005 Base Realignment and Closure ( BRAC ) recommendations , the Department of Defense recommended relocating the 91st Division to Fort Hunter Liggett . The four Brigades of the 91st Division were redesignated as separate brigades : The 91st Division moved its headquarters to Fort Hunter Liggett on 1 May 2009 . The 91st Division was reorganized and re - designated as the 91st Training Brigade ( Operations ) on 1 October 2009 . The 91st Training Brigade ( Operations ) was re - designated as the 91st Training Division ( Operations ) on 1 October 2010 . Famous Members . Army Catholic Chaplain William Borders was awarded the Bronze Star for Valor , while serving with the 362 Infantry Regiment in bitter fighting in Italy . He later became the Archbishop of Baltimore . References