These days, every modern army uses multiple rocket launchers that fire unguided rockets equipped with high-explosive warheads – often with devastating effects. The first such weapon – a 150mm, six-tube Nebelwerfer 41 – was delivered to the troops (German Wehrmacht) in 1940, after the Battle of France (a year before the Red Army fielded their own MLR – the famous Katyusha).
Unlike fin-stabilized (and thus highly inaccurate) Katyusha rockets, NbW 41 used spin-stabilized rockets (as all modern MLR do). The NbW 41 produced a tremendously lethal effect (both physical and psychological) on enemy troops (especially in urban combat) where a target area could be saturated by large-caliber, exploding rockets through indirect fire.
The Wehrmacht fielded several versions of Nebelwerfer, varying in caliber and in transportation method (most were towable, but some were vehicle-mounted, like the Soviet Katyusha). However, Germans mounted their Nebelwerfers not on trucks (as the Soviets did), but on Sd.Kfz. 251 half-trucks.
While their devastating anti-infantry capability was well-documented, the large rockets could also render certain combat tanks useless by injuring exposed crew, damaging hulls, and especially disabling track systems.
By the end of the war, over 5,000 launching units and over half a million rockets have been manufactured – and used extensively on both Eastern and Western fronts and in anti-guerilla operations.