[1] On 19 June 1916, the Ohioans were mobilized to defend the Mexico–United States border near El Paso, Texas, where they patrolled for 9 months.

This demobilization wouldn't last however, and the regiment, commanded by William Vance McMaken, was called up again 10 days later for service in World War I on 27 March 1917.

On 22 June 1918, the 74th Brigade (includes the 147th and 148th Infantry Regiments), departed from Newport News, Virginia, and arrived in France on 5 July.

The 37th and adjacent 79th Infantry Divisions advanced on heavy German positions and continued to push the enemy back.

The men of the regiment swam across the Boche River on 2 November in the face of enemy fire, and prepared to cross the Scheldt.

The Armistice of 11 November 1918 brought the fighting to an end, and the 147th camped at Le Mans, France until they returned home to Ohio on 19 April 1919.

[1] The 147th Infantry arrived at the port of New York on 25 March 1919 on the troopship USS Von Steuben and was demobilized on 19 April 1919 at Camp Sherman, Ohio.

By 8 February these units had reached Doma Cove, nine miles beyond the Poha River and the same distance short of Cape Esperance.

The 147th rooted out stubborn Japanese defenders and continued fighting after the island was officially declared secure on 1 August 1944.

Once the island was declared secure, the regiment was supposed to act as a garrison force, but they soon found themselves locked in a bitter struggle against thousands of stalwart defenders engaging in a last-ditch guerilla campaign to harass the Americans.

Some sources credit the regiment with killing at least 6,000 Japanese soldiers in those anonymous and merciless small unit actions.

[9] On 30 June 1945, the 1st Battalion boarded the USS Rockwall and was transported to the island of Tinian, where it earned the distinction of providing security for the Fat Man and Little Boy atomic bombs.

The 147th went on to fight in the bloody Battle of Okinawa, once again in charge of rooting out stubborn Japanese defenders who remained even after the island was declared secure.

[7] During World War II, the 147th Infantry Regiment fought in the battles of Guadalcanal, Saipan, Tinian, Iwo Jima, and Okinawa.

Aside from the combat on the battlefield, the 147th was also victim of little press coverage, fighting alongside Marines and the Navy, whose units commanded better public relations exposure.