Pentomic Era U.S. Army Division & Brigade Graphics

Graphics > American Orders of Battle > Pentomic Era U.S. Army (1957-1963)

This is a gallery of organizational graphics for Pentomic Era U.S. Army Divisions of the late 1950s and early 1960s, as well as the Army's one separate Combat Command (equivalent to an Armored Brigade) and Infantry Brigades. The 1956 organizational concepts were called ROCID for Infantry Divisions, ROTAD for Airborne Divisions, and ROCAD for Armored Divisions. Infantry Brigades (which replaced independent Regimental Combat Teams) had no unified table of organization, just notional examples, but they were generally scaled down versions of ROCID.

This does not cover the breadth of the 1950s and 1960s as the Army was organized along different concepts in the early- to mid-1950s and after 1963. This also does not necessarily cover every year of a division's Pentomic organization, as tweaks were made to the structure in 1959/1960. It also does not cover units organized along older pre-Pentomic tables even if they existed in the late 1950s. See the graphics for the specific year being covered.

One of the key features of the 1956 Tentative Pentomic TO&Es, what I'm calling the "first iteration" of Pentomic, was Battle Groups consisted of an HHC, 4 Rifle Companies and a 4.2" Mortar Battery. The Division Artillery also consisted of one 105mm Howitzer Battalion in direct support of Battle Groups (one battery per Battle Group) and one Rocket/Howitzer Battalion in general support (with two 155mm batteries, one 8-inch battery, and one Honest John Battery).

The refined 1959 D-series TO&Es, what I'm calling the "second iteration" of Pentomic, differed in that Infantry Battle Groups went to an HHC, 5 Rifle Companies and a Combat Support Company with mortars, recon, radar and assault weapons. However, Rifle Companies also went from an HQ, 4 Rifle Platoons and a Weapons Platoon to an HQ, 3 Rifle Platoons and Weapons Platoon under the second iteration. The change was more or less zero growth except for the new Rifle Company HQ. The DIVARTY was also changed to one composite 105mm/155mm Howitzer Battalion per Battle Group (each one 105mm and one 155mm battery), and the general support Rocket/Howitzer Battalion was reduced to just one 8-inch and one Honest John battery. So overall an increase in three 155mm howitzer batteries, but with 4 additional battalion headquarters.

Big credit to Mark Breed on the TOandEs email group who posted some of his U.S. Army unit station lists online, and to Walter Elkins at usarmygermany.com who has written a lot about this period for Germany-stationed units specifically. If you are interested in the California Army National Guard structure down to the company-level in the 1950s, Hathi Trust has very thorough reports on it (although if you're outside the U.S. you need a VPN to view them).

Airborne Divisions

11th Airborne Division (Augsburg, Germany, until July 1958)

Underwent ROTAD reorganization and CARS redesignation on 1 March 1957. Unit was already in Germany, having completed its Operation Gyroscope move replacing the 5th Infantry Division in April 1956. Inactivated on 1 July 1958 and elements transferred to the 24th Infantry Division.

82nd Airborne Division (Fort Bragg, NC)

Underwent ROTAD reorganization and CARS redesignation on 1 September 1957. As a result of the reflagging of the 11th Airborne Division into the 24th Infantry Division on 1 July 1958 and subsequent creation of a composite Airborne-Infantry Division in Germany (briefly the 24th, permanently the 8th), 2 of the 82nd Airborne's original 1957 Battle Groups (1-504 and 1-505) were transferred to the 8th Infantry Division in Dec 1958/Jan 1959. They were replaced by 2 Battle Groups (1-187 and 1-503) of the 24th Infantry Division (formerly 11th Airborne). In 1960, 2-503 Infantry was also transferred to the 25th Infantry Division and replaced by the reactivated 2-504 Infantry.

101st Airborne Division (Fort Campbell, KY)

Underwent ROTAD reorganization and CARS redesignation on 25 April 1957.

Armored Divisions (Active)

2nd Armored Division

No graphic

3rd Armored Division (Frankfurt, Germany)

Underwent ROCAD reorganization and CARS redesignation on 1 October 1957. The division was already in Germany, having replaced the 4th Infantry Division there in 1956 under Operation Gyroscope.

4th Armored Division (Göppingen, Germany)

Underwent ROCAD reorganization and CARS redesignation on 1 April 1957. Forward deployed to Germany beginning in November 1957 to January 1958 under Operation Gyroscope replacing the 2nd Armored Division.

Infantry Divisions (Active)

1st Cavalry Division (Tonggu, Korea)

Moved to Korea via the reflagging of the 24th Infantry Division in-place in October-November 1957, with elements concurrently reorganizing as a ROCID Pentomic division with CARS designations.

1st Infantry Division (Fort Riley, KS)

Reorganized as a ROCID Pentomic division on 15 February 1957. Designated as an element of STRAC. Converted into a cadre force for training recruits from 1958-1959 and taken off STRAC duty. All the 1st Infantry Division's original 1957 Battle Groups were transferred to the 8th and 24th Infantry Divisions, and replaced by the 8th Infantry Division's 5 original 1957 Battle Groups. Returned to combat and STRAC status as a result of the Berlin Crisis of 1961.

3rd Infantry Division

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4th Infantry Division (Fort Lewis, WA)

Reorganized as a ROCID Pentomic division on 1 April 1957. Designated as an element of STRAC.

7th Infantry Division

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8th Infantry Division (Bad Kreuznach, Germany)

Reorganized as a ROCID Pentomic division on 1 August 1957. Became a composite Airborne-Infantry Division in 1959 by the transfer of Battle Groups from the 82nd Airborne and 1st Infantry Divisions. Underwent D-series organizational tweaks in 1960.

9th Infantry Division

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10th Infantry Division

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24th Infantry Division (Augsburg, Germany, from July 1958)

Unit reconstituted in Germany as a (mostly) ROCID composite Airborne-Infantry Division by the reflagging of the 11th Airborne Division in July 1958. By 1959 was a ROCID Infantry Division, with the composite role transferring to the 8th Infantry Division. Prior to 15 October 1957, the 24th Infantry was a triangular Infantry Division in Korea. Its flag was transferred to Japan after its resources were used to reorganize the 1st Cavalry Division.

No graphic

25th Infantry Division

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Separate Combat Commands (Active)

Combat Command A, 1st Armored Division (Fort Polk, LA)

Organized as a separate Combat Command (equivalent to an armored brigade combat team) as the result of the rest of the 1st Armored Division being deactivated on 23 December 1957. Designated an element of STRAC.

Separate Infantry Brigades (Active)

2d Infantry Brigade (Fort Devens, MA)

Activated at Fort Devens, MA on 15 February 1958 to replace the 4th Regimental Combat Team. By 1960 underwent organizational tweaks with the issue of D-Series tables and designated an element of STRAC.

Armored Divisions (Guard/Reserve)

40th Armored Division (California ARNG)

Reorganized from the 40th Infantry Division and Southern California-based elements of the 111th Armored Cavalry Regiment on 1 July 1954. It underwent Pentomic reorganization and CARS reflagging on 5 June 1959. It was based in Southern California, primarily around Los Angeles.

Infantry Divisions (Guard/Reserve)

49th Infantry Division (California ARNG)

Organized on 5 August 1946 as the 52d Infantry Division and redesignated as the 49th Infantry Division on 31 October 1947. It underwent Pentomic reorganization and CARS reflagging on 28 April 1959. It was based in Northern California, particularly the San Francisco Bay Area and Central Valley.