The 349th Infantry arrived at the port of New York on 30 May 1919 on the troopship SS Ryndam and was demobilized on 12 June 1919 at Camp Dodge.

[2] The 349th Infantry was reconstituted in the Organized Reserve on 24 June 1921, assigned to the 88th Division, and allotted to the Seventh Corps Area.

For the 1937 Fourth Army maneuvers, the regiment provided a number of officers to the Iowa National Guard's 133rd Infantry at Camp Ripley, Minnesota.

The primary ROTC "feeder" schools for new Reserve lieutenants for the regiment were Coe College and the State University of Iowa.

The regiment underwent intensive basic and advanced training at Camp Gruber, and went on to score well in the various maneuvers it was tested in.

2LT John A. Liebenstein, K Company, of Monona, Iowa, earned the regiment's first Distinguished Service Cross by attacking an enemy Machine-gun nest with a jammed weapon.

[2] 2LT Liebenstein was wounded while taking a prisoner and bought his men time to escape as German mortar fire rained down.

[2]" Beginning in April, the 349th moved back into the line and continued to engage in active patrolling against enemy positions, where they perfected their tactics and captured prisoners for valuable intelligence gains.

Just before the end of the War in Europe, the 349th was briefly attached to the 103rd Infantry Division when they linked up in the Brenner Pass and drove into Austria against slight resistance.

[2] When World War II in Europe ended, the United Nations created the Free Territory of Trieste, which elements of the 88th Infantry Division were ordered to garrison.