Barrier troops

Barrier troops, blocking units, or anti-retreat forces are formations of soldiers that in some armies are placed behind regular troops on a battle line to prevent unauthorized withdrawal or retreat. Barrier troops are used to prevent unauthorized withdrawal of soldiers from the battlefield by any means, including indiscriminate killing. As troops guarding other units are obviously not available to fight the enemy they are a costly, often desperate, measure.

The concept of barrier troops dates from the earliest days of land warfare, when more experienced troops were regularly placed behind raw recruits to prevent panic and to provide a reserve if needed to stop an enemy advance. Roman legions were regularly backstopped by experienced triarii legionaries of many years' service.

During the Napoleonic Wars, the losses due to troops deserting battle were regularly greater than the losses resulting from combat. Since desertion was relatively easy in that era, the use of barrier troops enabled commanders to retain cohesive fighting units during the course of a long campaign.

In the Red Army of the Soviet Union, the concept of barrier troops first arose in August 1918 with the formation of the (zagraditelnye otriady), translated as "blocking troops" or "anti-retreat detachments" (Russian: заградотряды, заградительные отряды, отряды заграждения). The barrier troops were composed of personnel drawn from Cheka punitive detachments or from regular Red Army infantry regiments.

The first use of the barrier troops by the Red Army occurred in the late summer and fall on the Eastern front during the Russian Civil War, when commander Mikhail Tukhachevsky was authorized by War Commissar Leon Trotsky of the Communist Bolshevik government to station blocking detachments behind unreliable Red Army infantry regiments in the 1st Red Army, with orders to shoot if they either deserted or retreated without permission.

In December 1918 Trotsky ordered that additional barrier troops detachments be raised, for attachment to each infantry formation in the Red Army. On December 18 he cabled: "How do things stand with the blocking units? As far as I am aware they have not been included in our establishment and it appears they have no personnel. It is absolutely essential that we have at least an embryonic network of blocking units and that we work out a procedure for bringing them up to strength and deploying them." The barrier troops were also used to enforce Bolshevik control over food supplies in areas controlled by the Red Army, a role which soon earned them the hatred of the Russian civilian population.

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Wikipedia