On 22 November 1866, a Missouri Militia company known as the "Kansas City Guards" was organized at
Kansas City, Missouri. It was disbanded in April 1873. The company was reconstituted in the Missouri National Guard on 18 November 1887 as the "Kansas City Light Battery" and was redesignated on 18 December 1888, as Battery B, Artillery. It was disbanded on 6 November 1899. On 14 June 1905, Battery B was reconstituted in the Missouri National Guard, and on 4 February 1915, was consolidated with Battery A and Battery C, Artillery, to form the 1st Separate Battalion of Field Artillery. On 25 June 1916, the battalion was mustered into federal service for service on the
Mexican border, and was mustered out on 21–22 December 1916 at
Fort Riley,
Kansas. On 29 June 1917, the battalion was expanded and redesignated as the 2nd Regiment, Field Artillery. On 5 August 1917, the regiment was drafted into federal service for
World War I. On 1 October 1917, the regiment was redesignated the 129th Field Artillery Regiment and assigned to the
35th Division. The 129th is notable for its service in World War I, with
Battery D under the command of then-
Captain Harry S. Truman, later
President of the United States from 1945 to 1953. In recognition of this fact, this unit has the official designation "Truman's Own." The distinction of having had a battery that was commanded by a future U.S. president is also recognized by the presence of a battery designated "D", being the letter assigned to the battery Truman commanded, in lieu of a C Battery. The regiment was mustered out of service on 6 May 1919 at Fort Riley. The 129th Field Artillery was reconstituted in the National Guard on 29 July 1921, allotted to the state of Missouri, and assigned to the General Headquarters Reserve. The regiment was not called for in the modified National Guard manpower program issued in January 1923, and so was placed on the Deferred National Guard list and allotted to the Organized Reserve as the 418th Field Artillery Regiment (DNG). Although it was allotted to the state of South Dakota and was organized by 1924, with the abandonment of the Deferred List concept, the regiment was withdrawn from the Organized Reserve in 1927 and demobilized. On 27 June 1946, the unit was reconstituted in the Missouri National Guard as the 129th Field Artillery Battalion and assigned to the 35th Infantry Division. It was organized and federally recognized on 20 October 1947 with Headquarters at Maryville, Missouri. It was reorganized and redesignated on 15 April 1959 as the 129th Artillery, a parent regiment under the
Combat Arms Regimental System, to consist of the 1st Howitzer Battalion, an element of the 35th Infantry Division. Reorganized 1 April 1963 to consist of the 1st Howitzer Battalion. Reorganized 15 January 1968 to consist of the 1st Battalion. Redesignated 1 March 1972 as the 129th Field Artillery. Withdrawn 1 June 1989 from the Combat Arms Regimental System and reorganized under the
United States Army Regimental System. Redesignated 1 October 2005 as the 129th Field Artillery Regiment. ==Campaign participation credit==