U.S. Army Combat Arms Regimental System

The Combat Arms Regimental System (CARS), was the method of assigning unit designations to units of some of the combat arms branches (specifically, Infantry, including Special Forces, Field Artillery, and Armor) of the United States Army from 1957 to 1981. (Air Defense Artillery was added in 1968.) CARS was superseded by the U.S. Army Regimental System (USARS) in 1981.

Before the adoption of CARS, there was no satisfactory means of maintaining the active life of the combat arms organizations. Whenever the nation entered periods of military retrenchment, units were invariably broken up, reorganized, consolidated, or disbanded. During periods of mobilization, large numbers of new units were created. Changes in weapons and techniques of warfare produced new types of units to replace the old ones. As a result, soldiers frequently served in organizations with little or no history, while units with long combat records remained inactive.

In the late 1950s requirements for maneuverable and flexible major tactical organizations demanded highly mobile divisions with greatly increased firepower. For this purpose the regiment was deemed too large and unwieldy and had to be broken up into smaller organizations. (Most artillery and armored regiments had already been broken up for flexibility and maneuverability during World War II.)

When the U.S. Army division was reorganized under the Pentomic structure in 1957, the traditional regimental organization was eliminated, raising questions as to what the new units were to be called, how they were to be numbered, and what their relationship to former organizations was to be.

On 24 January 1957 the Secretary of the Army approved the CARS concept, as devised by the Deputy Chief of Staff for Personnel, which was designed to provide a flexible regimental structure that would permit perpetuation of unit history and tradition in the new tactical organization of divisions, without restricting the organizational trends of the future.

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