- Constituted 3 July 1946 in the Missouri Army National Guard as the 242d Engineer Battalion
- Organized and Federally recognized 4 August 1949 at Kansas City
- Converted and redesignated (less Company A) 1 March 1953 as Headquarters and Headquarters Company, 242d Transportation Battalion (Company A concurrently converted and redesignated as the 548th Transportation Truck Company - hereafters separate lineage)
- Converted and redesignated 15 April 1959 as Headquarters and Headquarters Detachment, 104th Replacement Battalion
- Converted and redesignated 1 April 1963 as Headquarters and Headquarters Detachment, 146th Engineer Battalion
- Reorganized and redesignated 15 January 1968 as Headquarters and Headquarters Company, 235th Engineer Group
- Reorganized and redesignated 1 September 1976 as the 235th Engineer Detachment
- Location changed 1 January 1984 to Nevada
- Location changed 1 May 1995 to Jefferson City
- Ordered into active Federal service 15 March 2003 at Jefferson City; released 7 July 2004 from active Federal service and reverted to state control
- Consolidated 1 April 2004 with Detachment 1, 235th Engineer Detachment (organized and Federally recognized 28 January 1998 and 10 February 1998 as Detachments 1 and 2, 235th Engineer Detachment) and consolidated unit designated as the 235th Engineer Detachment
- Consolidated 1 September 2006 with the 711th Transportation Detachment (see ANNEX), and consolidated unit deignated as Detachment 2, 735th Quartermaster Company
- Converted and redesignated 1 October 2010 as the 138th Support Company
- ANNEX
- Constituted 1 September 1991 in the Missouri Army National Guard as the 711th Transportation Company
- Organized and Federally recognized 24 October 1991 at Jefferson City
- Ordered into active Federal service 7 December 2003 at Jefferson City; released from active Federal service 3 June 2005 and reverted to state control
HOME STATION: Jefferson City