Schlieffen's ideas were largely aimed at operational-level leaders, that is, the commanders of Germany's divisions and army corps. The biggest problems in World War One, however, were at the lower, tactical level. And the German solution to these problems was to apply Schlieffen's operational principles to small units as well as to large ones. Thus, by decentralising command and by increasing the firepower of the infantry, they created a large number of platoon-sized units capable of independent action on the battlefield.
During this period, all the war's major combatants developed mechanized force theories. Theories of the Western Allies differed substantially from the Reichswehr's. British, French, and American doctrines broadly favored a more set-piece battle, less combined arms focus, and less focus on concentration. Early Reichswehr periodicals contained many translated works, though they were often not adopted. Technical advances in foreign countries were, however, observed and used in-part by the Weapons Office. Foreign doctrines are widely considered to have had little serious influence.
Guderian argued that the tank would be the decisive weapon of the next war. "If the tanks succeed, then victory follows", he wrote. In an article addressed to critics of tank warfare, he wrote "until our critics can produce some new and better method of making a successful land attack other than self-massacre, we shall continue to maintain our beliefs that tanks—properly employed, needless to say—are today the best means available for land attack." Addressing the faster rate at which defenders could reinforce an area than attackers could penetrate it during the First World War, Guderian wrote that "since reserve forces will now be motorized, the building up of new defensive fronts is easier than it used to be; the chances of an offensive based on the timetable of artillery and infantry co-operation are, as a result, even slighter today than they were in the last war." He continued, "We believe that by attacking with tanks we can achieve a higher rate of movement than has been hitherto obtainable, and—what is perhaps even more important—that we can keep moving once a breakthrough has been made."[154][l] Guderian additionally required that tactical radios be widely used to facilitate coordination and command by having one installed in all tanks.
Shipments of Jews to the camps had priority over anything but the army's needs on the German railways, and continued even in the face of the increasingly dire military situation at the end of 1942.[355] Army leaders and economic managers complained about this diversion of resources and the killing of skilled Jewish workers,[356] but Nazi leaders rated ideological imperatives above economic considerations.[357]
By the end of September, the SS had started to develop plans to deport Jews to newly invaded Poland: the first steps towards the systematic murder that would follow. In Poland itself, thousands of Poles and Jews were rounded up and shot, early indications of the systematic murder that would follow. Alongside this, Hitler approved a new programme of euthanasia to exterminate the handicapped and mentally ill.

The process of selection and murder was carefully planned and organized. When a train stopped at the platform, veteran prisoners received the victims and gathered their belongings in several barracks in an area known as “Kanada.” The arrivals were lined up in two columns – men and boys in one, women and girls in the other – and SS physicians performed a selection.  The criterion was the appearance of the prisoners, whose fate, for labor or for death, was determined at will. Before they entered the chamber, they were told that they were about to be disinfected and ordered to undress. The doors of the chamber were locked and the gas was introduced. After the victims were murdered, their gold teeth were extracted and women’s hair was shorn by the Sonderkommando – groups of Jews forced to work in the crematoria. The bodies were hauled to the crematorium furnaces for incineration, the bones were pulverized and the ashes were scattered in the fields.
In a blitzkrieg, tanks and troop-transport vehicles were concentrated, and massive attacks by dive bombers were conducted on enemy front-line positions. When these forces had broken through, they continued deep into enemy territory, encircling and cutting off the enemy. The techniques were first developed by the German army late in World War I in an effort to overcome static trench warfare, but the Germans lacked the mobility to succeed. Between the wars, armored tactics were further developed by Basil Liddell Hart and J. F. C. Fuller in Britain, Charles de Gaulle in France, and Heinz Guderian in Germany. Made chief of German mobile troops in 1938, Guderian led the drive across France in 1940.
General Erwin Rommel, who would later gain fame in the African desert as the "Desert Fox", led the 7th Panzer Division as it crashed through the Belgian defenses into France, skirting the Maginot Line and then smashing it from behind. This was a new kind of warfare integrating tanks, air power, artillery, and motorized infantry into a steel juggernaut emphasizing speedy movement and maximization of battlefield opportunities. Rommel kept a journal of his experiences. In this excerpt, he describes the action on May 14 as he leads a tank attack against French forces near the Muese River on the Belgian border:
The Third Reich first used concentration camps as places of unlawful incarceration of political opponents and other "enemies of the state". Large numbers of Jews were not sent there until after Kristallnacht in November 1938.[182] Although death rates were high, the camps were not designed as killing centers.[183] After war broke out in 1939, new camps were established, some outside Germany in occupied Europe.[184] In January 1945, the SS reports had over 700,000 prisoners in their control, of which close to half had died by the end of May 1945 according to most historians.[185] Most wartime prisoners of the camps were not Germans but belonged to countries under German occupation.[186]
The first mass transport to Auschwitz I, which included Catholic prisoners, suspected members of the Polish resistance, and 20 Jews, arrived on 14 June 1940 from prison in Tarnów, Poland. They were interned in the former building of the Polish Tobacco Monopoly, adjacent to the site, until the camp was ready.[24] By the end of 1940, the SS had confiscated land around the camp to create a 40-square-kilometre (15 sq mi) "zone of interest" surrounded by a double ring of electrified barbed wire fences and watchtowers.[25] The inmate population grew quickly as the camp absorbed Poland's intelligentsia and dissidents. By March 1941, 10,900 were imprisoned there, most of them Poles.[22]
The fire signaled the demise of German democracy. On the next day, the government, under the pretense of controlling the Communists, abolished individual rights and protections: freedom of the press, assembly, and expression were nullified, as well as the right to privacy. When the elections were held on March 5, the Nazis received nearly 44 percent of the vote, and with 8 percent offered by the Conservatives, won a majority in the government.
A concentration camp was established by the Nazis in the suburbs of the Polish towns of Oświęcim and Brzezinka which - like the rest of Poland - were occupied by the Germans from the beginning of the Second World War (1939) till it was liberated in 1945 near the war's end. The name of the city of Oświęcim was changed ('germanized') to Auschwitz, as well as the name of Brzezinka - Birkenau; which became the name of the camp as well.

Oskar Schindler (28 April 1908 – 9 October 1974) was a German industrialist and a member of the Nazi Party who is credited with saving the lives of 1,200 Jews during the Holocaust by employing them in his enamelware and ammunitions factories in occupied Poland and the Protectorate of Bohemia and Moravia. He is the subject of the 1982 novel Schindler's Ark and its 1993 film adaptation, Schindler's List, which reflected his life as an opportunist initially motivated by profit, who came to show extraordinary initiative, tenacity, courage, and dedication to save the lives of his Jewish employees.

×