Though its predecessor units have lineage that dates back before the American Civil War, the formation was not formally designated as the 20th Engineer Brigade until its activation on 16 August 1950, at Fort Leonard Wood, Missouri.

Reactivated on 1 May 1967, at Fort Bragg, the brigade deployed to South Vietnam where it supported American forces for several years and a dozen campaigns.

Comprising two battalions and six separate companies, the brigade provided engineer construction support to the Base Section of the European COMMZ in southwestern France.

In August 1954, it redeployed back to the United States and was activated at Fort Bragg, North Carolina, on 10 September 1954.

From that time until its inactivation on 12 December 1958, the brigade provided engineer support to the XVIII Airborne Corps.

During the Vietnam War, the brigade numbered over 13,000 officers and enlisted men organized into three engineer groups, with 14 battalions and 31 separate companies and detachments.

[9] The brigade provided all non-divisional engineer support in Military Regions III and IV during eleven campaigns.

[2] Units cleared more than one-half million acres (2,000 km2) of jungle, paved 500 kilometers of highway, and constructed bridges totaling more than six miles (10 km) in length.

[2] Since that time the brigade and its subordinate units supported the XVIII Airborne Corps, fulfilling critical combat engineer, construction, topographic, and bridging missions.

[8] In the wake of February 1976 Guatemalan earthquake, the brigade participated in humanitarian aid and rebuilding efforts of a major highway, CA-9.

[2] Over the years, the brigade has provided engineer support to XVIII Airborne Corps and other Army commands.

[11] The brigade completed 1,500 combat heavy battalions equivalent days of work constructing roads, airfields, heliports, ammunition/fuel/water storage points, life support areas and forward landing strips, distributed over ten million maps, trained over 5,000 coalition engineers, and supported the French attack on Assalman airfield.

[2] Other missions included repair of an airfield known as "Key West" by light equipment elements, support of the Long Range Surveillance Detachment, 313th Military Intelligence Battalion, 82nd Airborne Division based in Zakhu, located in Iraqi Kurdistan.

[17] As of May 2008, the brigade had constructed 10 major bridges and destroyed or captured IED cells in nine of the country's provinces.

Flowers,[21] Governor of the Panama Canal Zone Harold Parfitt,[22] Vice President of the United States and Nobel Peace Prize winner Al Gore,[9] Sergeant Major of the Army Leon L. Van Autreve,[23] and West Virginian state Senator Richard Ojeda.