Today the Force Structure and Unit History Branch continues the work begun by the Historical Section of the Army War College. The branch maintains historical information on active and inactive units in all components - Regular Army, Army Reserve, and Army National Guard, and prepares official Lineage and Honors Certificates. On the basis of research in primary and secondary material, the certificates outline the major organizational changes undergone by the unit and provide a list of the official battle honors (campaign credit and decorations) that the unit has earned. The information contained on the certificates is reformatted for publication in the Army Lineage Series

While it would take a book to recount the rich history brought about by the changes of each unit in the 1st Cavalry Division, an overall look at the major reorganizational elements of the Divisional lineage presents a picture of an organization that was accustomed to fighting and brought strength from change.

1st Cavalry Division - Organizational History
"As one of the Army's two on-call heavy contingency force divisions, the First Team has an on-order mission to deploy to a designated contingency area of operations by sea, air or land, conduct reception, staging, onward movement and integration; and on order, conduct combat operations and redeployment."
First-Team

22 January 1921; Constituted in the Regular Army as the 1st Cavalry Division. 13 September 1921; The 1st Cavalry Division was activated at Ft. Bliss, TX. 03 January 1933; 1st Cavalry Regiment was relieved from assignment to the 1st Cavalry Division. 04 December 1943; The 1st Cavalry Division was redesignated 1st Cavalry Division (Special) and reorganized partly under the Cavalry and partly under the Infantry Tables of Organization and Equipment. 20 July 1945; The assigned Regiments of the 1st Cavalry Division were organized wholly as Infantry, but retained their Cavalry designations. 25 March 1949; The 1st Cavalry Division reorganized as a Triangular Division. The 5th, 7th and 8th Cavalry Regiments were retained and the 12th Cavalry Regiment was deactivated. 01 November 1957; The 1st Cavalry Division was converted to the Pentomic structure with 5 Battle Groups. This change brought back the 12th Cavalry Regiment and added the 4th Cavalry Regiment as Battle Groups. 15 July 1963; The new Army Division called, Reorganization Objective Army Division (ROAD) brought back the triangular Division and from the point of the 1st Cavalry, resulted in the loss of the 4th and 12th Cavalry Battle Groups. 01 July 1965; The 1st Cavalry Division was reorganized as an Airmobile Division. The 9th Cavalry as well as the 12th Cavalry Regiments became part of the Division. 05 May 1971; The 1st Cavalry Division received an experimental designation as the TRICAP (Triple Capability) Division was organized with Armored, Infantry and Air Cavalry Brigade. 21 February 1975; The 1st Cavalry Division was designated an Armored Division, while retaining the historically, famous name of "Cavalry Division." 21 May, 1991 to 11 August, 1993; The 1st Cavalry Division initiated a series of unit reflagging and organizational changes to build a new contingency fighting force. 18 September, 2001 to 11 November, 2002: The 1st Cavalry Division initiated a series of unit change overs of the division organization and equipment replacements to support and field the FORCE XXI integrated combat system capabilities. 15 July, 2005; The 1st Cavalry Division was reorganized and transitioned to a (Modular) Modified Table of Organization and Equipment (MTOE) Unit of Action.

The Army did not begin a formal program for determining lineage and honors until the 1920s. Before that time, considerable confusion existed within the Army about the accepted procedures and methods for determining the prior history of units and their entitlement to battle honors. With the demobilization of the Army following World War I, many distinguished units were lost from the rolls. To avert such problems in the future, the Historical Section of the Army War College assumed responsibility for maintaining historical information about Army units: thus lineage work began.

Today the Force Structure and Unit History Branch continues the work begun by the Historical Section of the Army War College. The branch maintains historical information on active and inactive units in all components - Regular Army, Army Reserve, and Army National Guard, and prepares official Lineage and Honors Certificates. On the basis of research in primary and secondary material, the certificates outline the major organizational changes undergone by the unit and provide a list of the official battle honors (campaign credit and decorations) that the unit has earned. The information contained on the certificates is reformatted for publication in the Army Lineage Series.

The Army Lineage Series is one of the oldest series of volumes published by the Center of Military History. Over time, the scope and concept of the series have evolved considerably, but the purpose has remained the same: to provide a compact, readily available source of information on unit organizational history.

1st Cavalry Division - Command Units Lineage
First-Team

Headquarters and Tactical Command Posts
"First-Team" 20 August, 1921; Constituted in the Regular Army as Headquarters, 1st Cavalry Division. 13 September, 1921; Activated at Ft. Bliss, TX. 04 December, 1943; Reorganized and redesignated as Headquarters, 1st Cavalry Division, (Special). 25 March, 1949; Reorganized and redesignated as Headquarters, 1st Cavalry Division (Infantry). 01 July, 1960; Reorganized and redesignated as Headquarters and Headquarters Company, 1st Cavalry Division. 16 October, 2005; Reorganized and redesignated as Headquarters and Tactical Command Posts, 1st Cavalry Division.
Special Troops Battalion, 1st Cavalry Division
"Live The Legend" 06 September, 1921; Constituted in the Regular Army as the 1st Cavalry Division Train (Transportation Service), Quartermaster Corps. 20 September, 1921; Organized at Ft. Bliss, TX. as the 1st Cavalry Division Quartermaster Train. 01 May, 1936; Reorganized and redesignated as the 16th Quartermaster Squadron, an element of the 1st Cavalry Division. 15 March, 1943; Redesignated as the 16th Cavalry Quartermaster Squadron. 15 November, 1946; Squadron broken up and its elements converted, reorganized, and redesignated as follows: Headquarters and Headquarters Troop as Headquarters and Headquarters Troop, 16th Quartermaster Squadron. "A" Troop as the 18th Transportation Truck Troop; "B" Troop as the 19th Transportation Truck Troop; and "C" Troop as the 15th Quartermaster Pack Troop - hereafter separate lineages. 31 May, 1947; Headquarters and Headquarters Troop, 16th Quartermaster Squadron, inactivated in Japan. 25 March, 1949; Converted and redesignated as the 15th Replacement Company and remained an element of the 1st Cavalry Division. 25 September, 1949; Activated in Japan. 15 October, 1957; Reorganized and redesignated as the 15th Administration Company. 05 May, 1971; Reorganized and redesignated as the 15th Adjutant General Company. 15 September, 1985; Inactivated at Ft. Hood, TX. 16 October, 2005; Redesignated as Special Troops Battalion, 1st Cavalry Division, and activated at Ft. Hood, TX.
Headquarters, 1st Brigade Combat Team
"IronHorse" 29 August, 1917; Constituted in the Regular Army as Headquarters, 1st Cavalry Brigade. February, 1918; Organized in at Ft. Sam Houston, TX, as an element of the 15th Cavalry Division. 12 May, 1918; Relieved from assignment to the 15th Cavalry Division. 14 July, 1919; Demobilized at Brownsville, TX. 20 August, 1921; Reconstituted in the Regular Army as Headquarters, 1st Cavalry Brigade, and assigned to the 1st Cavalry Division (later redesignated as the 1st Cavalry Division, Special). 01 September, 1921; Organized at Camp Harry J. Jones, AZ. 25 March, 1949; Inactivated in Japan and relieved from assignment to the 1st Cavalry Division, Special. 20 May, 1949; Converted and redesignated as Headquarters, 1st Constabulary Brigade, and activated in Germany. 15 August, 1951; Inactivated in Germany. 05 December, 1951; Disbanded. 15 July, 1963; Reconstituted in the Regular Army as Headquarters and Headquarters Company, 1st Brigade, 1st Cavalry Division. 01 September, 1963; Activated in Korea. 17 October, 2005; Headquarters, 1st Brigade, 1st Cavalry Division, reorganized and redesignated as Headquarters, 1st Brigade Combat Team, 1st Cavalry Division (Headquarters Company, 1st Brigade, 1st Cavalry Division - hereafter separate lineage).
Special Troops Battalion, 1st Brigade Combat Team
"Strength Thru Courage" 29 August, 1917; Constituted in the Regular Army as Headquarters, 1st Cavalry Brigade. February, 1918; Organized in at Ft. Sam Houston, TX, as an element of the 15th Cavalry Division. 12 May, 1918; Relieved from assignment to the 15th Cavalry Division. 14 July, 1919; Demobilized at Brownsville, TX. 20 August, 1921; Reconstituted in the Regular Army as Headquarters, 1st Cavalry Brigade, and assigned to the 1st Cavalry Division (later redesignated as the 1st Cavalry Division, Special). 01 September, 1921; Organized at Camp Harry J. Jones, AZ. 25 March, 1949; Inactivated in Japan and relieved from assignment to the 1st Cavalry Division, Special. 20 May, 1949; Converted and redesignated as Headquarters, 1st Constabulary Brigade, and activated in Germany. 15 August, 1951; Inactivated in Germany. 05 December, 1951; Disbanded. 15 July, 1963; Reconstituted in the Regular Army as Headquarters and Headquarters Company, 1st Brigade, 1st Cavalry Division. 01 September, 1963; Activated in Korea. 17 October, 2005; Headquarters Company, 1st Brigade, 1st Cavalry Division, reorganized and redesignated as Special Troops Battalion, 1st Brigade Combat Team, 1st Cavalry Division (Headquarters, 1st Brigade, 1st Cavalry Division - hereafter separate lineage).
Headquarters, 2nd Brigade Combat Team
"BlackJack" 29 August, 1917; Constituted in the Regular Army as Headquarters, 2nd Cavalry Brigade. 27 December, 1917; Organized at Ft. Bliss, TX, as an element of the 15th Cavalry Division. 12 May, 1918; Relieved from assignment to the 15th Cavalry Division. 09 July, 1919; Demobilized at Ft. Bliss, TX. 20 August, 1921; Reconstituted in the Regular Army as Headquarters, 2nd Cavalry Brigade, and assigned to the 1st Cavalry Division (later redesignated as the 1st Cavalry Division, Special). 14 September, 1921; Organized at Ft. Bliss, TX. 25 March, 1949; Inactivated in Japan and relieved from assignment to the 1st Cavalry Division, Special. 20 May, 1949; Converted and redesignated as Headquarters, 2nd Constabulary Brigade, and activated in Germany. 15 December, 1951; Inactivated in Germany. 15 July, 1963; Converted and redesignated as Headquarters and Headquarters Company, 2nd Brigade, 1st Cavalry Division. 01 September, 1963; Activated in Korea. 17 October, 2005; Headquarters, 2nd Brigade, 1st Cavalry Division, reorganized and redesignated as Headquarters, 2nd Brigade Combat Team, 1st Cavalry Division (Headquarters Company, 2nd Brigade, 1st Cavalry Division - hereafter separate lineage).
Special Troops Battalion, 2nd Brigade Combat Team
"Preservation Thru Strength & Courage" 29 August, 1917; Constituted in the Regular Army as Headquarters, 2nd Cavalry Brigade. 27 December, 1917; Organized at Ft. Bliss, TX, as an element of the 15th Cavalry Division. 12 May, 1918; Relieved from assignment to the 15th Cavalry Division. 09 July, 1919; Demobilized at Ft. Bliss, TX. 20 August, 1921; Reconstituted in the Regular Army as Headquarters, 2nd Cavalry Brigade, and assigned to the 1st Cavalry Division (later redesignated as the 1st Cavalry Division, Special). 14 September, 1921; Organized at Ft. Bliss, TX. 25 March, 1949; Inactivated in Japan and relieved from assignment to the 1st Cavalry Division, Special. 20 May, 1949; Converted and redesignated as Headquarters, 2nd Constabulary Brigade, and activated in Germany. 15 December, 1951; Inactivated in Germany. 15 July, 1963; Converted and redesignated as Headquarters and Headquarters Company, 2nd Brigade, 1st Cavalry Division. 01 September, 1963; Activated in Korea. 17 October, 2005; Headquarters Company, 2nd Brigade, 1st Cavalry Division, reorganized and redesignated as Special Troops Battalion, 2nd Brigade Combat Team, 1st Cavalry Division (Headquarters, 2nd Brigade, 1st Cavalry Division - hereafter separate lineage).
Headquarters, 3rd Brigade Combat Team
"GreyWolf" 29 August, 1917; Constituted in the Regular Army as Headquarters, 3rd Cavalry Brigade. December, 1917; Organized in at Camp Harry J. Jones, AZ, as an element of the 15th Cavalry Division. 12 May, 1918; Relieved from assignment to the 15th Cavalry Division. 15 July, 1919; Demobilized at Camp Harry J. Jones, AZ. 20 August, 1921; Reconstituted in the Regular Army as Headquarters, 3rd Cavalry Brigade, and assigned to the 2nd Cavalry Division. 15 October, 1940; Activated at Ft. Riley, KS. 15 July, 1942; Relieved from assignment to the 2nd Cavalry Division; concurrently converted and redesignated as Headquarters, 9th Armored Division Trains. 13 October, 1945; Inactivated at Camp Patrick Henry, VA. 15 July, 1963; Relieved from assignment to the 9th Armored Division; concurrently converted and redesignated as Headquarters, 3rd Brigade, 1st Cavalry Division. 01 September, 1963; Headquarters, 3rd Brigade 1st Cavalry Division activated in Korea. 15 September, 1980; Headquarters, 3rd Brigade 1st Cavalry Division inactivated at Ft. Hood, TX. 21 May, 1991; Headquarters, 3rd Brigade 1st Cavalry Division activated at Ft. Hood, TX. 17 October, 2005; Reorganized and redesignated as Headquarters, 3rd Brigade Combat Team, 1st Cavalry Division.
Special Troops Battalion, 3rd Brigade Combat Team
"Steadfast & Vigilant" 20 August, 1921; Constituted in the Regular Army as Headquarters Troop, 3d Cavalry Brigade, and assigned to the 2nd Cavalry Division. 21 February, 1941; Activated at Ft. Riley, KS. 15 July, 1942; Relieved from assignment to the 2nd Cavalry Division; concurrently converted and redesignated as Headquarters Company, 9th Armored Division Trains. 13 October, 1945; Inactivated at Camp Patrick Henry, VA. 15 July, 1963; Relieved from assignment to the 9th Armored Division; concurrently converted and redesignated as Headquarters Company, 3d Brigade, 1st Cavalry Division. 01 September, 1963; Activated in Korea. 15 September, 1980; Inactivated at Ft. Hood, TX. 21 May, 1991; Activated at Ft. Hood, TX. 17 October, 2005; Reorganized and redesignated as Special Troops Battalion, 3d Brigade Combat Team, 1st Cavalry Division.
Headquarters, 4th Brigade Combat Team
"LongKnife" 15 May, 1971; Constituted in the Regular Army as Headquarters and Headquarters Company, 4th Brigade, 1st Cavalry Division, and activated at Ft. Hood, TX. 30 June; 1972; Inactivated at Ft. Hood, TX. 16 October, 2005; Headquarters, 4th Brigade, 1st Cavalry Division, redesignated as Headquarters, 4th Brigade Combat Team, 1st Cavalry Division, and activated at Ft. Bliss, Texas (Headquarters Company, 4th Brigade, 1st Cavalry Division - hereafter separate lineage).
Special Troops Battalion, 4th Brigade Combat Team
"Viligant & Always Ready" 15 May, 1971; Constituted in the Regular Army as Headquarters and Headquarters Company, 4th Brigade, 1st Cavalry Division, and activated at Ft. Hood, TX. 30 June, 1972; Inactivated at Ft. Hood, TX. 16 October, 2005; Headquarters Company, 4th Brigade, 1st Cavalry Division, redesignated as Special Troops Battalion, 4th Brigade Combat Team, 1st Cavalry Division, and activated at Ft. Bliss, TX (Headquarters, 4th Brigade, 1st Cavalry Division - hereafter separate lineage).
1st Air Cavalry Brigade Combat Team
"Warriors" 01 September, 1984; Constituted in the Regular Army as Headquarters and Headquarters Troop, Cavalry Brigade, 1st Cavalry Division, and activated at Ft. Hood, TX. 16 October, 1996; Reorganized and redesignated as Headquarters and Headquarters Company, Aviation Brigade, 1st Cavalry Division. 26 May, 2005; Inactivated at Ft. Hood, TX. 26 May, 2005; Constituted in the Regular Army as Headquarters and Headquarters Company, 1st Air Cavalry Brigade, 1st Cavalry Division, and activated at Ft. Hood, TX using the assets of the Combat Aviation Brigade.

Over the years, in which the 1st Cavalry Division was engaged in the development of a sub-set of organizations and their supporting equipment, several units were organized, activated and assigned to the Division. In the evolution of the Division, some of these units were deactivated and relieved from assignment and newly organized units (with a different skill set or equipments) replaced them.

These units that formally served, contributed significantly to the combat effectiveness, played key roles in the battlefield accomplishments and evolutionary organizational restructuring of the 1st Cavalry Division are

1st Cavalry Division - Legacy Command Units Lineage
First-Team

Headquarters and Headquarters Company, Division Support Command
"WagonMasters" 22 August, 1957; Constituted in the Regular Army as Headquarters and Headquarters Detachment, 1st Cavalry Division Trains. 01 November, 1957; Activated in Korea. 01 September, 1963; Consolidated with the 1st Cavalry Division Band (organized in 1856) and consolidated unit reorganized and redesignated as Headquarters, Headquarters Company and Band, 1st Cavalry Division Support Command. 05 May, 1971; Reorganized and redesignated as Headquarters and Headquarters Company, 1st Cavalry Division Support Command (Band concurrently withdrawn from the 1st Cavalry Division Support Command - hereafter separate lineage). 06 July, 2005; Division Support Command (DISCOM) of the 1st Cavalry Division was inactivated and redesignated the 15th Sustainment Brigade - hereafter separate lineage.
Headquarters and Headquarters Company, 15th Sustainment Brigade
"Support The Action" 22 August, 1957; Constituted in the Regular Army as Headquarters and Headquarters Detachment 1st Cavalry Division Trains. 01 November, 1957; Activated in Korea. Consolidated with the 1st Cavalry Division Band (organized in 1856) and consolidated unit reorganized and redesignated as Headquarters, Headquarters and Band, 1st Cavalry Division Support Command. 15 November, 1967; Redesignated as Headquarters, Headquarters Company and Band, 1st Cavalry Division Support Command. 05 May, 1971; Reorganized and redesignated (less band - hereafter separate lineage) as Headquarters and Headquarters Company, 1st Cavalry Division Support Command. 17 October, 2005; Consolidated with Headquarters and Headquarters Company, 15th Support Brigade (see ANNEX - below) and consolidated unit designated as Headquarters and Headquarters Company, 15th Sustainment Brigade (organic elements concurrently constituted and activated). ANNEX: 04 May, 1966; Constituted in the Regular Army as Headquarters and Headquarters Company, 15th Support Brigade 01 July, 1966; Activated at Ft. Hood, TX. 20 October, 1967; Inactivated in Vietnam. 21 September, 1968; Activated at Ft. Lewis, WA. 21 March, 1973; Inactivated at Ft. Lewis, WA.
Headquarters and Headquarters Battery, Division Artillery
"The Red Team" 01 November 1940; Constituted as Headquarters and Headquarters Battery, 1st Cavalry Division Artillery. 03 January 1941; Activated at Ft. Bliss, TX. 04 December 1943; Redesignated Headquarters and Headquarters Battery, 1st Cavalry Division Artillery (Special) and reorganized partly under the Cavalry and partly under the Infantry Tables of Organization and Equipment. 25 March 1949; Reorganized as a Triangular Division and designation as Headquarters and Headquarters Battery, 1st Cavalry Division remained the same. 20 June, 2005; Inactivated at Ft. Hood, TX.
Headquarters and Headquarters Detachment, Engineer Brigade
"Sappers Forward" 16 October 1991; Constituted in the Regular Army as Headquarters and Headquarters Detachment, Engineer Brigade, 1st Cavalry Division 28 April 1992; Provisionally organized under the Engineer Restructure Initiative of the US Army as Headquarters and Headquarters Detachment, Engineer Brigade, 1st Cavalry Division. 16 October 1992; Headquarters and Headquarters Detachment, Engineer Brigade, 1st Cavalry Division activated at Ft. Hood, TX. 24 May 2005; Headquarters and Headquarters Detachment, Engineer Brigade, 1st Cavalry Division inactivated at Ft, Hood, TX.