Blitzkrieg sought decisive actions at all times. To this end, the theory of a schwerpunkt (focal point) developed; it was the point of maximum effort. Panzer and Luftwaffe forces were used only at this point of maximum effort whenever possible. By local success at the schwerpunkt, a small force achieved a breakthrough and gained advantages by fighting in the enemy's rear. It is summarized by Guderian as "Nicht kleckern, klotzen!" ("Don't tickle, smash!")
By Guderian's account he single-handedly created the German tactical and operational methodology. Between 1922 and 1928 Guderian wrote a number of articles concerning military movement. As the ideas of making use of the combustible engine in a protected encasement to bring mobility back to warfare developed in the German army, Guderian was a leading proponent of the formations that would be used for this purpose. He was later asked to write an explanatory book, which was titled Achtung Panzer! (1937). In it he explained the theories of the tank men and defended them.
By mid-1944 those Jewish communities within easy reach of the Nazi regime had been largely exterminated, in proportions ranging from about 25 percent in France to more than 90 percent in Poland. On 5 May Himmler claimed in a speech that "the Jewish question has in general been solved in Germany and in the countries occupied by Germany". As the Soviet armed forces advanced, the camps in eastern Poland were closed down, with surviving inmates shipped to camps closer to Germany. Efforts were made to conceal evidence of what had happened. The gas chambers were dismantled, the crematoria dynamited, and the mass graves dug up and the corpses cremated. Local commanders continued to kill Jews, and to shuttle them from camp to camp by forced "death marches". Already sick after months or years of violence and starvation, some were marched to train stations and transported for days at a time without food or shelter in open freight cars, then forced to march again at the other end to the new camp. Others were marched the entire distance to the new camp. Those who lagged behind or fell were shot. Around 250,000 Jews died during these marches.
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.