Pistols, rifles, carbines, submachine guns, machine guns, and AT rifles equipped engineer, reconnaissance and regular infantry units. Smaller explosives supplemented them (grenades, explosive charges, smoke charges and in the case of sappers, mines).
Anti-tank artillery (high-velocity, direct-fire mode guns)
Infantry guns (low-velocity, direct fire mode guns)
Field artillery (low-velocity howitzers, requiring forward observers to spot targets when firing in indirect fire mode )
Mortars (low-velocity pieces with indirect fire).
On 22 June 1941, almost all artillery was towed even in armored divisions, but self-propelled artillery started to appear in small quantities: rocket launchers mounted on trucks (called Katyushas by the Soviets), AT and infantry guns on Panzer I chassis, AA 20mm guns on half-tracks and assault guns using the Panzer III chassis (StuG III). The trend for more self-propelled artillery would continue during the war.
Armored half-tracks for the infantry
These vehicles complemented the combat units by pulling artillery guns, transporting infantry, and carrying supplies and other gear.
Combat troops, which did most of the fighting.
Communication troops, that supported combat troops by intertwining the command, communication and control networks necessary for commanders to fight the battles. They received radio and telephone/teleprinter equipment for that purpose.
Supply troops, operating in the rear areas, enabled combat and communication troops to carry out their tasks by furnishing food, fuel, lubricants, ammunition, spare parts, and other equipment. Motor-transport and railroad troops constitute the bulk of the supply troops .
The division stood as the most fundamental combat unit. Each division corresponded to a self-contained small army able to fight and supply itself if an army railhead existed less than 200 kilometers (125 miles) behind.
Supreme commanders measured the size of their armies in divisions, rather than in men because this better reflected the capabilities of the armed forces. For the invasion of Russia, the Germans deployed infantry, armored, motorized infantry, SS motorized infantry, mountain, cavalry, jäger, and security divisions. The first four types amounted to almost 90% of the total. The Soviets likewise organized infantry, armored, motorized, and cavalry divisions. The latter represented only 3% of the total.
Of note is the lack of German and Soviet parachute divisions . The Soviets deployed parachute brigades, however (a formation smaller than a division but larger than a regiment).
The size, organization and equipment of a division reflected the mission of the unit according to the operational doctrine established by its respective army.THE ARMORED DIVISIONS
Out of 151 divisions that the Germans deployed against the Red Army, only 19 were Panzer divisions (17 immediately available and 2 in reserve). Despite the small share of the overall force structure (13%), these fully mobile formations, along with the Luftwaffe, played a decisive role in the offensive Blitzkrieg doctrine. The highly-trained and well-equipped armored divisions had the mission to pierce the enemy’s ground defenses and to penetrate through the gap to encircle large, slow-moving enemy armies.
They possessed the mobility to swiftly concentrate force at decisive times and places, and the firepower to deliver a formidable blow to enemy’s defenses smashing them open . Designed to impart a high tempo to its maneuvers, it kept the enemies, whose operational rhythm was slower, always one step behind and therefore off-balance.
The Panzer regiment of 2 or 3 tank battalions made up the core of the panzer division . During the Great War, abundant machine gun nests proved capable of defeating almost any attack on its tracks, but contemporary tanks enjoyed immunity against machine gunfire. Even the lightest of German tanks incorporated 13mm of hardened, homogeneous armor which was impervious to armor-piercing bullets fired from rifle-caliber machine guns . A mass of tanks on the attack repeatedly defeated an outnumbered anti-tank defense returning the mobility to the battlefield. Based on a study of its performance in battle, the Germans modified the organization of the armored division frequently. At the outset of the war, it included a panzer brigade of 340 tanks in two regiments. Deemed too large, the Wehrmacht reduced the brigade for the battle against France to 258 tanks. By the time of Barbarossa, the Germans had eliminated the brigade command, leaving the division with only 1 panzer regiment totaling 206 tanks on average .
This change stemmed from Hitler’s resolution to double the number of panzer divisions and the incapacity of the German industry to manufacture enough tanks in time, which forced the reduction of the panzer regiments per division in half . Once the production of tanks increased, the OKH planned to reintroduce the second panzer regiment. Despite this decrease in tanks, the new 1941 panzer division demonstrated in practice to be a highly effective formation, and likely superior to its 1939 and 1940 predecessors. The Germans would never restore the second panzer regiment.
Two reasons explain this outcome, one involving the tanks themselves and the other, the organization of the supporting arms.
The quality of the German tanks had improved markedly since the invasion of Poland. In September 1939 only 11% of the tanks in the panzer divisions were medium-weight Pz. Kpfw. III and IV. The light Pz. Kpfw. I and II accounted for 78% of the German tank park while the balance consisted of small numbers of Pz. Kpfw. 35(t), 38(t) and command tanks.
The tank modernization program could boast significant improvements by 22 June 1941. Pz. Kpfw. III and IV proportion increased to 42%, Pz. Kpfw 35(t) and 38(t) to 23%, while the light Pz. Kpfw. I and II decreased to 35% .
This qualitative increase conferred the 1941 panzer divisions much more striking power.
To boost the effectiveness of the panzers, the Germans assigned fully motorized supporting elements that could keep pace with them. Armored combat vehicles were inherently powerful but had crucial operational limitations. Certain types of terrain could restrict their movement: rivers, lakes, mountains, gorges, thick forests, swamps, and man-made obstacles, among others, posed significant difficulties. An armored engineer battalion was an integral part of the panzer division to remove barriers and to construct bridges and other suitable corridors thus restoring mobility. It also helped to destroy field fortifications that could not be neutralized by the tank’s guns. Three Engineer companies (1 armored and 2 motorized), one “K” bridge train and a motorized column carrying all supplies constituted the battalion.
Tanks could capture ground, but they could not mop-up conquered territory or defend it against infiltration, especially at night. During an attack, their limited visibility prevented the swift identification of every enemy’s camouflaged positions. Motorized or armored infantry helped them overcome these defensive and offensive deficiencies. The Germans stumbled upon the optimal ratio of infantry to tanks at about this time: 2 infantry battalions per every tank battalion. Thus, the German panzer division contained 2 motorized infantry regiments, each composed of 2 motorized infantry battalions, to support its single panzer regiment .
The Soviet and Anglo-American armies would later arrive at the same organization and even though they had at their disposal much more tanks than the Germans, they kept this infantry-to-tank ratio .
Divisional artillery support took the form of a motorized artillery regiment composed of two light field artillery battalions equipped with 105mm howitzers and one medium field artillery battalion furnished with 150mm howitzers. These guns could deliver significant firepower on stubborn defenders, helping the panzers to overcome strong defensive positions.
Forward observers in armored vehicles moved behind the first wave of tanks to spot targets and radioed their coordinates to the artillery commanders . In this way, the artillery batteries rained fire on the selected objectives very rapidly. The observers also corrected the fire to improve accuracy.
Spotter aircraft attached to panzer divisions flew above the battlefield identifying targets (with an emphasis on enemy artillery) and correcting fire over a depth inaccessible to ground observers.
Luftwaffe observers in armored vehicles also moved behind the first wave and could call for expedite aircraft strikes on clearly identifiable and suitable targets.
A reconnaissance motorcycle battalion , moving ahead of the main body, detected enemy positions, captured important bridges or communication junctions and identified and marked suitable routes of advance to bypass the enemy or simply to move most efficiently.
The Luftwaffe also attached one observation Staffel to every panzer division to provide tactical and battlefield reconnaissance. In this manner, the panzer commander had at his disposal extremely valuable intelligence on the location and forward and rearward displacements of enemy units as well as information on empty sectors and on the nature of terrain over which his formation would move.
This information also allowed the commander to prepare his defenses with enough time in case of an enemy counterattack and to deploy troops on the most vulnerable sectors opposite to the enemy axis of attack while simultaneously enabling him to deliver spoiling assaults when and where the enemy was more vulnerable (i.e. an open flank during the march).
German fighters would roam the airspace above trying to prevent enemy aerial reconnaissance from observing the panzer troops, giving the Germans the advantage of surprise while the enemy was presented with uncertainty at every time.
An armored anti-tank (AT) battalion formed an integral part of the division and had the mission to contain enemy tank attacks. German doctrine dictated that tankmen should avert tank versus tank combat and attract the enemy towards their AT defense. German tanks usually fell behind their own AT guns when attacked by the adversary’s armor.
This AT battalion contained a motorized AT company with towed 37mm and 50mm guns and one flak (anti-aircraft) company composed of self-propelled light 20mm guns . It also included one self-propelled company of AT guns or infantry guns mounted on Pz. Kpfw. I chassis.
An organic mobile signals battalion with radio and telephone companies had the mission to construct the command, communication and control network that allowed the commanding officers to come up with a clear picture of the situation and to distribute appropriate orders.
Finally, and of decisive importance, the divisional services contained fully motorized units that provided the combat troops with the necessary supplies to move, live and fight, adjusting their capacity to the changing conditions. They were organized in such a way that the division could be broken up into two or more self-sufficient teams.
The German divisional commander would regularly organize all-arms combat teams (known as Kampfgruppen), whose size depended on the intended objectives. They could be battalion or more frequently brigade size. A typical Kampfgruppe would consist of one tank battalion, two infantry battalions, one engineer company, an artillery battalion, a signals company and their respective supply trains under a single leader. A panzer division frequently split into two brigade-sized Kampfgruppen moving along different routes when necessary . These ad-hoc task forces could be reorganized at will depending on the situation faced by the commander.
Overall, a German panzer division controlled 14,373 men, and its equipment included between 162 and 239 tanks, 1.183 motorcycles, 2.546 motor vehicles, 18 armored cars, 12 AA guns, 28 AT guns, 6 SP AT guns, 30 x 81mm mortars, 6 SP infantry guns, and 58 artillery pieces .
Besides, each of these large formations included one attached (as opposed to organic) reconnaissance Staffel under divisional command providing intelligence well ahead of the line of advance of the division .
Among all divisional size formations present in the Wehrmacht, the Panzer division stood as the most powerful one, but even so, it rarely operated singly. To increase its shock power, the Wehrmacht combined 2 armored divisions and one motorized infantry division into a motorized corps (the term panzerkorps appeared until 1943). When the Germans launched Barbarossa, they deployed 10 motorized corps, 6 of which presented this organization. Of the rest, three contained only one panzer and one motorized infantry division, while the last boasted 2 armored divisions, 2 motorized infantry divisions, and 1 cavalry division, making it the largest of them all.
During the Battle of France, the Germans deployed for the first time a panzergruppe , a small-size fully motorized army of 3 motorized corps. Its remarkable success led to the deployment of 4 panzergruppen for the invasion of Russia, two containing 2 motorized corps and the other two equipped with 3.
The Panzergruppen were fearsome elite formations possessing overwhelming firepower and mobility. These large, fully mobile armies numbering 80,000 to 140,000 men did not have an equivalent anywhere else in the world at the time and each one went into battle with the support of one Fliegerkorps, a large formation of combat aircraft capable of pummeling the enemy ground units in front of the German forces and able to clear the skies of enemy aircraft.
Compared with the organization of the panzer division which stood close to the optimum for the war the Soviet tank division remained tank-heavy, lacking infantry. It included 6 tank battalions and only 3 motorized infantry battalions. Completely equipped , it included 11.343 men, 210 T-34 medium tanks, 63 KV-1 heavy tanks, 26 BT-7 light tanks, 22 T-26 light tanks, 54 T-26 flamethrower tanks, 56 BA-10 heavy armored cars, 39 BA-20 light armored cars, 28 field guns, 12 AA guns, and 54 mortars. It also contained around 1.372 motor vehicles and 37 motorcycles .
The Red Army tank division incorporated fewer men than the Panzer division but with a larger armored contingent that provided a significant advantage in firepower (weight of a broadside). Without the advantage of hindsight, it appeared as powerful as the panzer division, but in the crucible of combat this unbalanced organization did not prove successful and it had to be modified early in the campaign. Overall the Russians fielded 50 tank divisions, the largest body of armor in the world by a considerable margin. Two tanks divisions and one motorized division formed a mechanized corp. These mechanized corps remained the largest assemblage of armor in the Soviet army in 1941. The Soviets did not introduce the tank army until mid-1942 .
25 of these mechanized corps appeared in the western order of battle of the Red Army opposite the German army.
THE MOTORIZED DIVISIONS
The German motorized infantry division lacked a tank element . Some sources erroneously indicate that it included a panzer battalion , but in 1941 this was not the case. Later in the war, the Germans did include this armored battalion in the formation and renamed it Panzergrenadiere division.
The 1941 motorized division was equipped with 2 motorized infantry regiments, each one containing 3 infantry battalions (two more than the panzer division). The addition of this fully motorized infantry division, (which had the same mobility as a panzer division), to the corps, allowed it to better defend a sector or to carry out small-scale mop-up operations. When the Panzer divisions achieved an encirclement, their scarce infantry turned out insufficient to prevent the enemy from finding thinly defended spots and escape. The motorized divisions greatly helped to improve matters.
The Germans employed 10 army and 3 SS motorized infantry divisions for the invasion.
The Soviet motorized division differed from its German counterpart by including a sizable armored body, a tank regiment of 5 light tank battalions. Since it also included 6 motorized infantry battalions, its tank-to-infantry ratio was better balanced than the tank division and demonstrated more resiliency in combat. The RKKA’s 25 motorized divisions in its order of battle outnumbered the Wehrmacht motorized divisions by a factor of almost two to one.
INFANTRY AND RIFLE DIVISIONS
Infantry divisions remained the backbone of both armies. The order of battle shows 101 German infantry divisions and 139 Soviet rifle divisions. Both were organized along similar lines. 3 regiments with 3 infantry battalions, plus supporting troops. The German division included an artillery regiment, an anti-tank battalion, an engineer battalion, a signal battalion, and a reconnaissance battalion, plus divisional services and headquarters. It contained 17.200 men, 5.375 horses, 1.133 horse-drawn vehicles, 942 trucks, and 452 motorcycles. In terms of firepower, it counted with 3 armored cars, 75 AT guns, 11 light AA guns, 142 mortars, and 74 heavier artillery pieces. In general, it could defend itself forcefully.
Infantry division’s unspectacular job was nonetheless vital: consolidate the encirclements created by the panzers, prevent the surrounded troops to escape, and mop up, eliminating them from the enemy’s order of battle. Divisions were organized in corps of two to four divisions. An army had three to five army corps and it could include a Panzergruppe of 2 to 3 motorized corps.
Compared with its counterpart, the Soviet rifle division was similarly organized but had somewhat less personnel, it contained fewer small arms, had less motorization, and had a diminished AT defense. Its AA component was similar, and it was more powerfully equipped with artillery. It also included a light tank company as part of the reconnaissance battalion. The 1941 Rifle division organization that started the war would not survive long. Within weeks of the invasion, it would be completely reorganized, making it smaller to facilitate the job of the less experienced Soviet officers.
The table below describes how the German and Soviet infantry divisions evolved during the war to face the increased challenges thrown at them.