Although the term shock troop became popular in the 20th century, the concept is not a new one, see for example the use by Napoleonic era armies of the Forlorn hope. Presently, the term is rarely used explicitly, as the strategic concepts behind it have become standard contemporary military thinking (see section After World War II).
During the American Civil War, 1861-65, the elite Iron Brigade and Irish Brigade of the Union's Army of the Potomac, and the Texas Brigade, Stonewall Brigade and the Louisiana Zouaves (also known by their nickname,Louisiana Tigers) of the Confederacy's Army of Northern Virginia were considered to be shock troops.
Notwithstanding the postwar status of the Storm Troopers in German service, the same sort of tactical doctrine was widely espoused in British and French service in late 1917 and 1918, with variable results. The British Army standard training manual for platoon tactics, SS 143, was used from February 1917 onwards and contained much of what was standard for German shock troops. According to Ward, the Australian and Canadian divisions deployed amongst British forces in France quickly came to be regarded as the best shock troops in the Allied ranks due to their ferocity in battle, and were employed accordingly..
However, the first successful use of this tactics in the battle take a place on Eastern front, in July 1917, applied by Czechoslovak legionaries in the Battle of Zborov. The success in battle resulted from special skills of legionaries, previously used mostly in reconnaissance actions.
During World War II the Red Army of the Soviet Union deployed five Shock armies. Many of the units which spearheaded the Soviet offensives on the Eastern Front from the Battle of Stalingrad to the Battle of Berlin were Shock Armies. Shock Armies had high proportions of infantry, engineers and field artillery, but with less emphasis on operational mobility and sustainability. Soviet assaults which were expected to lead to very high casualties were often lead by penal battalions. Soviet Shock Armies were characterized by a higher allocation of army-level artillery units to break German defense positions by weight of fire, and often had heavy tank regiments or heavy self-propelled gun regiments to add additional direct fire support. Once a breach in the enemy tactical position was made, more mobile units such as tank and mechanized corps would be inserted through the Shock Army's positions with the mission of penetrating deep into the enemy rear area. By the end of the war, though, Soviet Guards Armies typically enjoyed superior artillery support to that of the shock armies.
Well-known Shock Armies include the 2nd Shock Army, which spearheaded several offensives in the Leningrad area, and the 3rd Shock Army, which played a key role in the Battle of Berlin.
A Soviet ad hoc combat group was a mixed arms unit of about eighty men in assault groups of six to eight men, closely supported by field artillery. These were tactical units which were able to apply the tactics of house to house fighting that the Soviets had been forced to develop and refine at each Festungsstadt (fortress city) they had encountered from Stalingrad to Berlin.