[1] The 2nd Maine was recalled into Federal Service on 18 June 1916, and served along the Mexico–United States border in Texas to guard against hostile raids.

The bloodied New Englanders continued the fight at the Battle of Saint-Mihiel,[2] and in the momentous Meuse-Argonne Offensive, the largest and bloodiest operation of the war for the American Expeditionary Forces.

The regiment was inducted into active federal service on 24 February 1941 and moved to Camp Blanding, Florida, where it arrived on 13 March 1941.

[5] After finishing training at Camp Shelby, Mississippi, they were sent to the Pacific Theater to fight against the Empire of Japan.

The 43rd Division made a westward advance against the Japanese airfield at Munda and covered the southern (coastal) flank of the drive.

The Battle of Munda Point was extremely bloody for the regiment; progress was slow and casualties were high, but eventually the area was captured on 5 August 1943, effectively ending all organized Japanese resistance on the island.

As the left wing of the invasion force, they pushed inland, encountering stiff opposition from fanatical Japanese enemies.

[6] The 103rd fought for about a month in the breakout operations from Lingayen, and finally received a week long rest in February.

Both the 103rd Infantry and the 152nd Field Artillery Regiment (both from the Maine Army National Guard) received the Philippine Republic Presidential Unit Citation for their daring actions during the Battle of Luzon.