Assault troops

Shock troops or assault troops are formations created to lead an attack. They are often better trained and equipped than other infantry, and expected to take heavy casualties even in successful operations.

"Shock troop" is a calque, a loose translation of the German word Stoßtrupp. Military units which contain assault troops are typically organized for mobility with the intention that they will penetrate through enemy defences and attack into the enemy's vulnerable rear areas.

Although the term "shock troop" became popular in the 20th century, the concept is not a new one, such as the utilization by Western European armies of the forlorn hope. Presently, the term is rarely used as the strategic concepts behind it have become standard contemporary military thinking.

Several sources describes how the Vikings used berserkers as shock troops in organized warfare.

In late-medieval Europe the German Landsknecht and Swiss mercenaries used large Zweihänder swords to break into pike formations.

Grenadiers originated as specialized assault soldiers for siege operations. First established with a distinct role in the mid- to late-17th century, grenadier units would throw grenades and storm breaches while leading the forefront of a breakthrough. Even after abandoning the use of the original black-powder grenade, armies retained the grenadier companies and regiments as specialist assault troops.

The American Civil War (1861-1865) saw units of shock troops fielded both by the Army of the Potomac and by the Confederate Army of Northern Virginia. The Iron Brigade and Irish Brigade spearheaded many of the Union's most dangerous attacks. For the CSA, the Texas Brigade and Virginia's Stonewall Brigade had similar functions. In the course of campaigning all of these élite units suffered heavy casualties, with their roles being eliminated several times over.

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