Constituted 13 January 1941 in the Regular Army as the 3rd Armored Regiment and assigned to the 3rd Armored Division.

Activated 15 April 1941 at Camp Beauregard, Louisiana.

Redesignated 8 May 1941 as the 33rd Armored Regiment.

Inactivated 10 November 1945 in Germany.

Regiment broken up 7 July 1947 and its elements redesignated as follows:
Regimental Headquarters and Headquarters Company, Headquarters and Headquarters Company, 1st Battalion, and Companies A, D, E, and F as the 33rd Tank Battalion, and remained assigned to the 3rd Armored Division.

Headquarters and Headquarters Company, 3rd Battalion, and Companies G and H as the Service Company and Companies B and C, respectively, 7th Tank Battalion, and remained assigned to the 3rd Armored Division (remainder of the 7th Tank Battalion organized from elements of the 32nd Armored Regiment).

Headquarters and Headquarters Company, 2nd Battalion, Companies B, C, and I, Service and Maintenance Companies, and Band disbanded.

(Reconnaissance Company as Troop E, 83rd Mechanized Cavalry Reconnaissance Squadron—hereafter separate lineage).

After 7 July 1947 the above units underwent changes as follows:
7th and 33rd Tank Battalions activated 15 July 1947 at Fort Knox, Kentucky.
Reorganized and redesignated 30 July 1948 as the 7th and 33rd Medium Tank Battalions, respectively.
Reorganized and redesignated 15 March 1955 as the 7th and 33rd Tank Battalions, respectively.
7th and 33rd (less Company D) Tank Battalions inactivated 1 October 1957 in Germany and relieved from assignment to the 3rd Armored Division.

Headquarters and Headquarters Company, 2nd Battalion; Service Company; and Companies B, C, and I, 33rd Armored Regiment, reconstituted 28 May 1948 in the Regular Army as Headquarters, Headquarters and Service Company, and Companies B, C, and A, respectively, 62nd Heavy Tank Battalion.
62nd Heavy Tank Battalion assigned 18 June 1948 to the 10th Infantry Division.
Activated 1 July 1948 at Fort Riley, Kansas.
Reorganized and redesignated 15 June 1954 as the 62nd Tank Battalion.
Inactivated 1 July 1957 in Germany.
Relieved 1 October 1957 from assignment to the 10th Infantry Division.

Maintenance Company, 33rd Armored Regiment, reconstituted 1 October 1957 in the Regular Army.

33rd and 62nd Tank Battalions; Headquarters and Service Company and Companies B and C, 7th Tank Battalion; and Maintenance Company, 33rd Armored Regiment, consolidated 1 October 1957 and consolidated unit reorganized and redesignated as the 33rd Armor, a parent regiment under the Combat Arms Regimental System.

Withdrawn 16 April 1987 from the Combat Arms Regimental System and reorganized under the United States Army Regimental System.

Activated 16 April 1987 at Fort Lewis, Washington using personnel and equipment from the 2nd Battalion, 77th Armor.
 Assigned 15 August 1988 to the 9th Infantry Division.
 Inactivated 28 September 1990 at Fort Lewis, Washington, and relieved from assignment to the 9th Infantry Division.
 Assigned 16 February 1991 to the 199th Infantry Brigade and activated at Fort Lewis, Washington.
 Relieved 16 July 1992 from assignment to the 199th Infantry Brigade.
Components of 2nd Battalion 33rd Armor attached 194th (separate) Armor Brigade Fort Knox 1993.
 Inactivated 14 January 1994 at Fort Polk, Louisiana.
 Assigned 16 April 1995 to the 2nd Infantry Division and activated at Fort Lewis, Washington using personnel and equipment from the 3rd Battalion, 77th Armor.

Redesignated as 33rd Cavalry Regiment "Cav Men of War" effective 28 June 2005 and assigned to 3rd Brigade Combat Team -"Rakkasans" 101st Airborne Division (Air Assault) at Fort Campbell, Kentucky.
1-33 Cavalry continues the lineage of 1-33 Armor.
Constituted 13 January 1941 in the Regular Army as the 3rd Armored Regiment and assigned to the 3rd Armored Division.
Activated 15 April 1941 at Camp Beauregard, Louisiana.
Redesignated 8 May 1941 as the 33rd Armored Regiment.
Inactivated 10 November 1945 in Germany.
Regiment broken up 7 July 1947 and its elements redesignated as follows:
Regimental Headquarters and Headquarters Company, Headquarters and Headquarters Company, 1st Battalion, and Companies A, D, E, and F as the 33rd Tank Battalion, and remained assigned to the 3rd Armored Division.
Headquarters and Headquarters Company, 3rd Battalion, and Companies G and H as the Service Company and Companies B and C, respectively, 7th Tank Battalion, and remained assigned to the 3rd Armored Division (remainder of the 7th Tank Battalion organized from elements of the 32nd Armored Regiment).
Headquarters and Headquarters Company, 2nd Battalion, Companies B, C, and I, Service and Maintenance Companies, and Band disbanded.
(Reconnaissance Company as Troop E, 83rd Mechanized Cavalry Reconnaissance Squadron—hereafter separate lineage).
After 7 July 1947 the above units underwent changes as follows:
7th and 33rd Tank Battalions activated 15 July 1947 at Fort Knox, Kentucky. Reorganized and redesignated 30 July 1948 as the 7th and 33rd Medium Tank Battalions, respectively. Reorganized and redesignated 15 March 1955 as the 7th and 33rd Tank Battalions, respectively. 7th and 33rd (less Company D) Tank Battalions inactivated 1 October 1957 in Germany and relieved from assignment to the 3rd Armored Division.
Headquarters and Headquarters Company, 2nd Battalion; Service Company; and Companies B, C, and I, 33rd Armored Regiment, reconstituted 28 May 1948 in the Regular Army as Headquarters, Headquarters and Service Company, and Companies B, C, and A, respectively, 62nd Heavy Tank Battalion. 62nd Heavy Tank Battalion assigned 18 June 1948 to the 10th Infantry Division. Activated 1 July 1948 at Fort Riley, Kansas. Reorganized and redesignated 15 June 1954 as the 62nd Tank Battalion. Inactivated 1 July 1957 in Germany. Relieved 1 October 1957 from assignment to the 10th Infantry Division.
Maintenance Company, 33rd Armored Regiment, reconstituted 1 October 1957 in the Regular Army.
33rd and 62nd Tank Battalions; Headquarters and Service Company and Companies B and C, 7th Tank Battalion; and Maintenance Company, 33rd Armored Regiment, consolidated 1 October 1957 and consolidated unit reorganized and redesignated as the 33rd Armor, a parent regiment under the Combat Arms Regimental System.
Withdrawn 16 April 1987 from the Combat Arms Regimental System and reorganized under the United States Army Regimental System.
Activated 16 April 1987 at Fort Lewis, Washington using personnel and equipment from the 2nd Battalion, 77th Armor.  Assigned 15 August 1988 to the 9th Infantry Division.  Inactivated 28 September 1990 at Fort Lewis, Washington, and relieved from assignment to the 9th Infantry Division.  Assigned 16 February 1991 to the 199th Infantry Brigade and activated at Fort Lewis, Washington.  Relieved 16 July 1992 from assignment to the 199th Infantry Brigade. Components of 2nd Battalion 33rd Armor attached 194th (separate) Armor Brigade Fort Knox 1993.  Inactivated 14 January 1994 at Fort Polk, Louisiana.  Assigned 16 April 1995 to the 2nd Infantry Division and activated at Fort Lewis, Washington using personnel and equipment from the 3rd Battalion, 77th Armor.
Redesignated as 33rd Cavalry Regiment "Cav Men of War" effective 28 June 2005 and assigned to 3rd Brigade Combat Team -"Rakkasans" 101st Airborne Division (Air Assault) at Fort Campbell, Kentucky. 1-33 Cavalry continues the lineage of 1-33 Armor.
33rd Armor Regiment