The 123rd Infantry Regiment is a unit within the United States Army, specifically part of the Army National Guard. It was activated during World War I and has since seen service in various conflicts, including both World Wars and more recently, Operation Iraqi Freedom. Originally organized in 1917, the regiment consists of multiple battalions spread across several states, primarily in the Midwest and Southeast regions of the United States. The 123rd Infantry Regiment's mission is to provide ready forces for prompt employment in defense of the state, territory, or nation when called upon. It operates under the authority of the Army National Guard's 34th Infantry Division.