Blitzkrieg, meaning lightning war in German, is an offensive, fast attack strategy used extensively during World War II.
The roots of the blitzkrieg are hard to pin as it is somewhat vague as to what exactly a blitzkrieg is. Generally it is an attack led by a mechanized units into an enemy defense were infantry comes in afterwards to "mop up." It should be noted that Blitzkrieg cannot be classified as a single tactic or strategy but instead a mix of tactics. In fact, Blitzkrieg was almost never referred to directly by German documents and typically saved for propaganda. Therefore, one cannot say that Blitzkrieg was a favored tactic among many a commander, but the methodology may have been. The characteristics of what later became Blitzkrieg however are as follows.
The first stage is a continuous bombardment by mobile artillery and aircraft, namely the Stuka dive bomber. This bombing would often be concentrated on strategic targets such as airfields and forms of communications. These attacks would also cause great fear among civilian populations further adding to the present chaos. Lack of communications, evacuating civilians, and the overall pace and ferocity of the attacks would cause mass confusion in the defenders lines. This confusion would assist in the spreading of false rumors, lower troop moral, weaken defenses, and make a less effective combat unit overall.
The second stage would be a tank led attack. The tanks would be used to spearhead the attack and deliver a very swift and devastating blow to the enemy before they can regroup and reorganize. The tank led rush would be very effective as German tank technology was far advanced at the beginning of the war and the present anti-tank defenses were often quite few and ineffective. Also, the countries being attacked would often be suited well for tank warfare with flat open plains with decent weather.
Lastly infantry would sweep in clearing out any stragglers. Following the rest of the mechanized unit these troops were often transported in vehicles such as half tracks, motorcycles, and others. These tactics combined formed a very formidable strategy that proved very effective in the early stages of the war.
Blitzkrieg found use for multiple reasons. The Germans learning from WWI wanted to avoid long defensive warfare which often ended up stalemating. The swiftness of the attack also made organization and communications poor and ineffective for the defenders. The fast pace of the attack also helped the economy not suffer as it prevented the war from becoming a long continues line of battles with high casualties and equipment loss. The physiological effect was also effective on the enemy as it made defenders nervous as they never knew when an attack would come and tactics such as spies spreading rumors and the infamous siren on Stukas enhanced this. Blitzkrieg was mainly developed by Heinz Guderian, a German general who was sturdying closely British tank warfare demonstrations and theories.
As the war dragged on the Blitzkrieg's effectiveness began to fade. The German army along with its many problems such as its two front war, supply draining, etc. also was being countered while using the blitz. The Allies began developing new technologies that countered the blitzkreg such as developing more effective anti-tank weapons, more effective communications, more numerous and effective tanks such as the Russian T-34, etc. Furthermore, as Germany lost air superiority, the dive bombers that were critical to the tactic of combined arms could not fly to their targets. The Blitzkrieg also had the shock of its attack wear off as troops prepared for it more effectively.
The view that the Blitzkrieg would have been planned by Hitler has been refuted in historical research. The historical expert Karl-Heinz Frieser calls it a "myth".