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.
In late January 1945, SS and police officials forced 4,000 prisoners to evacuate Blechhammer on foot. Blechhammer was a subcamp of Auschwitz-Monowitz. The SS murdered about 800 prisoners during the march to the Gross-Rosen concentration camp. SS officials also killed as many as 200 prisoners left behind in Blechhammer as a result of illness or unsuccessful attempts to hide. After a brief delay, the SS transported around 3,000 Blechhammer prisoners from Gross-Rosen to the Buchenwald concentration camp in Germany.
Some Auschwitz prisoners were subjected to inhumane medical experimentation. The chief perpetrator of this barbaric research was Josef Mengele (1911-79), a German physician who began working at Auschwitz in 1943. Mengele, who came to be known as the “Angel of Death,” performed a range of experiments on detainees. For example, in an effort to study eye color, he injected serum into the eyeballs of dozens of children, causing them excruciating pain. He also injected chloroform into the hearts of twins, to determine if both siblings would die at the same time and in the same manner.
Each of the trains carried in excess of a thousand victims. Prisoners had been packed into cattle wagons with no room to sit, no food and two buckets: one for water and another to use as a toilet. The journey could last days on end, with the prisoners not knowing where they were passing through or where they were going. Many victims died during the journey as a result of suffocation, illness or hunger.

British theorists John Frederick Charles Fuller and Captain Basil Henry Liddell Hart have often been associated with the development of blitzkrieg, though this is a matter of controversy. In recent years historians have uncovered that Liddell Hart distorted and falsified facts to make it appear as if his ideas were adopted. After the war Liddell Hart imposed his own perceptions, after the event, claiming that the mobile tank warfare practised by the Wehrmacht was a result of his influence.[142] By manipulation and contrivance, Liddell Hart distorted the actual circumstances of the blitzkrieg formation, and he obscured its origins. Through his indoctrinated idealisation of an ostentatious concept, he reinforced the myth of blitzkrieg. By imposing, retrospectively, his own perceptions of mobile warfare upon the shallow concept of blitzkrieg, he "created a theoretical imbroglio that has taken 40 years to unravel."[143] Blitzkrieg was not an official doctrine and historians in recent times have come to the conclusion that it did not exist as such.[a]

SS officers, including the infamous Dr. Josef Mengele, would conduct selections among these lines, sending most victims to one side and thus condemning them to death in the gas chambers. A minority was sent to the other side, destined for forced labor. Those who were sent to their deaths were killed that same day and their corpses were burnt in the crematoria. Those not sent to the gas chambers were taken to “quarantine,” where their hair was shaved, striped prison uniforms distributed, and registration took place. Prisoners’ individual registration numbers were tattooed onto their left arm.
1 Auschwitz I. The first camp to be used (therefore called Stammlager, 'main camp' in German). It is in a far more complete state than Birkenau, but is also much smaller. The camp consists of former Polish military barracks, which were requisitioned by the Nazis in 1940. Near the entrance, you will see the wrought iron gate bearing the infamous and mocking camp slogan, Arbeit macht frei - "work sets you free." Inside some of them you will find information material, boards, photos and personal belongings to illustrate the life and cruelties of this camp. The only remaining gas chamber is here. As indicated in the chamber, it was reconstructed to its wartime layout after the war. Other sights include solitary confinement cells used as punishment, the death wall memorial where several thousands of people were shot by firing squad, and a reconstruction of the gallows used in 1947 to execute camp commandant Rudolf Höss, on the site of the camp's Gestapo office.  edit
At the three Reinhard camps the victims were killed by the exhaust fumes of stationary diesel engines.[279] Gold fillings were pulled from the corpses before burial, but the women's hair was cut before death. At Treblinka, to calm the victims, the arrival platform was made to look like a train station, complete with fake clock.[300] Majdanek used Zyklon-B gas in its gas chambers.[301] In contrast to Auschwitz, the three Reinhard camps were quite small.[302] Most of the victims at these camps were buried in pits at first. Sobibór and Bełżec began exhuming and burning bodies in late 1942, to hide the evidence, as did Treblinka in March 1943. The bodies were burned in open fireplaces and the remaining bones crushed into powder.[303]
On 7 November 1938, Herschel Grynszpan, a Polish Jew, shot the German diplomat Ernst vom Rath in the German Embassy in Paris, in retaliation for the expulsion of his parents and siblings from Germany.[118][k] When vom Rath died on 9 November, the government used his death as a pretext to instigate a pogrom against the Jews throughout the Third Reich. The government claimed it was spontaneous, but in fact it had been ordered and planned by Hitler and Goebbels, although with no clear goals, according to David Cesarani; the result, he writes, was "murder, rape, looting, destruction of property, and terror on an unprecedented scale".[120][121]
Uniquely at Auschwitz, prisoners were tattooed with a serial number, on their left breast for Soviet prisoners of war[97] and on the left arm for civilians.[98] Categories of prisoner were distinguishable by triangular pieces of cloth (German: Winkel) sewn onto on their jackets below their prisoner number. Political prisoners (Schutzhäftlinge or Sch), mostly Poles, had a red triangle, while criminals (Berufsverbrecher or BV) were mostly German and wore green. Asocial prisoners (Asoziale or Aso), which included vagrants, prostitutes and the Roma, wore black. Purple was for Jehovah's Witnesses (Internationale Bibelforscher-Vereinigung or IBV)'s and pink for gay men, who were mostly German.[99] An estimated 5,000–15,000 gay men prosecuted under German Penal Code Section 175 (proscribing sexual acts between men) were detained in concentration camps, of which an unknown number were sent to Auschwitz.[100] Jews wore a yellow badge, the shape of the Star of David, overlaid by a second triangle if they also belonged to a second category. The nationality of the inmate was indicated by a letter stitched onto the cloth. A racial hierarchy existed, with German prisoners at the top. Next were non-Jewish prisoners from other countries. Jewish prisoners were at the bottom.[101]
Blitzkrieg (German: "lightning war") is a method of fast-moving, air-and-land warfare first used extensively during World War II. German armies invading Poland in 1939 used tanks, armored trucks, self-propelled guns, and dive bombers to break through opposing forces and penetrate far behind their lines. During the invasion of the Low Countries and France in 1940, the German armored columns again used these tactics to shock and disorganize the defenders. On the Allied side, U.S. general George S. Patton exhibited (1944) particular skill in mobile warfare in Europe.
As Nazi tyranny spread across Europe, the Germans and their collaborators persecuted and murdered millions of other people. Between two and three million Soviet prisoners of war were murdered or died of starvation, disease, neglect, or brutal treatment. The Germans targeted the non-Jewish Polish intelligentsia for killing, and deported millions of Polish and Soviet civilians for forced labor in Germany or in occupied Poland, where these individuals worked and often died under deplorable conditions.

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.
Use of armored forces was crucial for both sides on the Eastern Front. Operation Barbarossa, the German invasion of the Soviet Union in 1941, involved a number of breakthroughs and encirclements by motorized forces. Its stated goal was "to destroy the Russian forces deployed in the West and to prevent their escape into the wide-open spaces of Russia." This was generally achieved by four panzer armies which encircled surprised and disorganized Soviet forces, followed by marching infantry which completed the encirclement and defeated the trapped forces. The first year of the Eastern Front offensive can generally be considered to have had the last successful major blitzkrieg operations.
Schindler’s profits were extraordinarily high because he used low-paid Jewish workers from the ghetto the Nazis established in the city. During the war, many industrialists like Schindler used the forced labor of Jews living in Nazi ghettos or concentration camps. Major German companies, including Volkswagen, Bayer, and IG Farben, the largest chemical company in the world at the time, profited handsomely from coerced labor. This labor often occurred in the worst conditions possible, and many workers died as a result of being subjected to excessively long, arduous work shifts without adequate food.

^ Many of the German participants of Operation Citadel made no mention of blitzkrieg in their characterisation of the operation. Several German officers and commanders involved in the operation wrote their account of the battle after the war, and some of these postwar accounts were collected by the US Army. Some of these officers are: Theodor Busse (Newton 2002, pp. 3–27), Erhard Raus (Newton 2002, pp. 29–64), Friedrich Fangohr (Newton 2002, pp. 65–96), Peter von der Groeben (Newton 2002, pp. 97–144), Friedrich Wilhelm von Mellenthin (Mellenthin 1956, pp. 212–234), Erich von Manstein (Manstein 1983, pp. 443–449), and others.
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.
May 16, 1944 - Jews from Hungary arrive at Auschwitz. Eichmann arrives to personally oversee and speed up the extermination process. By May 24, an estimated 100,000 have been gassed. Between May 16 and May 31, the SS report collecting 88 pounds of gold and white metal from the teeth of those gassed. By the end of June, 381,661 persons - half of the Jews in Hungary - arrive at Auschwitz.
During World War I, Fuller had been a staff officer attached to the new tank corps. He developed Plan 1919 for massive, independent tank operations, which he claimed were subsequently studied by the German military. It is variously argued that Fuller's wartime plans and post-war writings were an inspiration or that his readership was low and German experiences during the war received more attention. The German view of themselves as the losers of the war, may be linked to the senior and experienced officers' undertaking a thorough review, studying and rewriting of all their Army doctrine and training manuals.[148]

Several SS personnel oversaw the killings at each gas chamber, while the bulk of the work was done by the mostly Jewish prisoners known as Sonderkommandos (special squads).[91][92] Hungarian doctor Miklós Nyiszli reported that the Sonderkommando numbered around 860 prisoners when the Hungarian Jews were being killed in May–July 1944.[93] Their responsibilities included removing goods and corpses from the incoming trains, guiding victims to the dressing rooms and gas chambers, and working in the "Canada" barracks, where the victims' possessions were stored.[94] Housed separately from other prisoners, in somewhat better conditions, their quality of life was further improved by access to the goods taken from murdered prisoners, which they were sometimes able to steal and trade on Auschwitz's black market.[95] Many Sonderkommandos committed suicide in response to the horrors of their work; others were generally shot by the SS in a matter of weeks. New Sonderkommando units were formed from incoming transports. Almost none of the 2,000 prisoners placed in these units survived to the camp's liberation.[96]

In the summer of 1942, when Germany launched another offensive in the southern USSR against Stalingrad and the Caucasus, the Soviets again lost tremendous amounts of territory, only to counter-attack once more during winter. German gains were ultimately limited by Hitler diverting forces from the attack on Stalingrad itself and seeking to pursue a drive to the Caucasus oilfields simultaneously as opposed to subsequently as the original plan had envisaged.

Once a strategic target had been selected, Stuka dive bombers were sent in to ‘soften’ up the enemy, destroy all rail lines, communication centres and major rail links. This was done as the German tanks were approaching and the planes withdrew only at the last minute so that the enemy did not have time to recover their senses when the tanks attacked supported by infantry. 
To achieve a breakout, armored forces themselves would attack the enemy's defensive line directly, supported by their own infantry (Panzergrenadiers), artillery fire and aerial bombardment in order to create a breach in the enemy's line. Through this breach the tanks could break through without the traditional encumbrance of the slow logistics of a pure infantry regiment. The breaching force never lost time by 'stabilising its flanks' or by regrouping; rather it continued the assault in a towards the interior of the enemies lines, sometimes diagonally across them. This point of breakout has been labeled a "hinge", but only because a change in direction of the defender's lines is naturally weak and therefore a natural target for blitzkrieg assault.
In October 1941, work began on Auschwitz II, or Birkenau, located outside the nearby village of Brzezinka. There the SS later developed a huge concentration camp and extermination complex that included some 300 prison barracks; four large so-called Badeanstalten (German: “bathhouses”), in which prisoners were gassed to death; Leichenkeller (“corpse cellars”), in which their bodies were stored; and Einäscherungsöfen (“cremating ovens”). Another camp (Buna-Monowitz), near the village of Dwory, later called Auschwitz III, became in May 1942 a slave-labour camp supplying workers for the nearby chemical and synthetic-rubber works of IG Farben. In addition, Auschwitz became the nexus of a complex of 45 smaller subcamps in the region, most of which housed slave labourers. During most of the period from 1940 to 1945, the commandant of the central Auschwitz camps was SS-Hauptsturmführer (Capt.) and ultimately SS-Obersturmbannführer (Lieut. Col.) Rudolf Franz Hoess (Höss).
On 31 July 1941, Hermann Göring gave written authorization to Reinhard Heydrich, Chief of the Reich Security Head Office (RSHA), to prepare and submit a plan for Die Endlösung der Judenfrage (the Final Solution of the Jewish question) in territories under German control and to coordinate the participation of all involved government organizations.[152] Plans for the extermination of the European Jews—eleven million people—were formalized at the Wannsee Conference in Berlin on 20 January 1942. Some would be worked to death and the rest killed.[153] Initially the victims were killed with gas vans or by Einsatzgruppen firing squads, but these methods were impractical for an operation of this scale.[154] By 1942, killing centers at Auschwitz, Sobibór, Treblinka, and other extermination camps had become the primary method of mass killing.[155]
"Rothenburg [a subordinate tank commander] now drove off through a hollow to the left with the five tanks which were to accompany the infantry, thus giving these tanks a lead of 100 to 150 yards. There was no sound of enemy fire. Some 20 to 30 tanks followed up behind. When the commander of the five tanks reached the rifle company on the southern edge of Onhaye wood, Colonel Rothenburg moved off with his leading tanks along the edge of the wood going west. We had just reached the southwest corner of the wood and were about to cross a low plantation, from which we could see the five tanks escorting the infantry below us to our left front, when suddenly we came under heavy artillery and anti-tank gunfire from the west. Shells landed all round us and my tank received two hits one after the other, the first on the upper edge of the turret and the second in the periscope.
Instead, Marcel Goldberg, a Jewish “clerk” assigned to the new Plaszow commandant Arnold Buscher, played the largest role in compiling the transport list. It is generally agreed that Buscher, an SS officer, “could not have cared, within certain numerical limits, who went on the list,” according to Thomas Keneally. It’s also agreed that Goldberg engaged in a certain amount of corruption in who he added to the list and, moreover, that there was not even one “list” but rather different lists that emerged over a series of months.
You find the stories of Irena Sendler, who defied the Nazis and saved 2,500 Jewish children by smuggling them out of the Warsaw Ghetto .. Maria von Maltzan, who risked everything to defy Hitler and the Nazi Régime .. Miep Gies, who risked her life daily to hide Anne Frank and her family .. the Rescue of the Danish Jews, Varian Fry, the American Schindler,  Kurt Gerstein SS Officer, the site Courage and Survival ..
Reading the comments below, it is interesting to see how little people know about history and what actually happened during WW2. Is the education system so bad in America that one person doesn't know that Poland was invaded in 1939 by the Nazi - pick up a book! The lesson of Auschwitz should be learnt, but once should also realise that it wasn't just the Jews who were murdered. There were gypsies, native poles, political opponents, homosexuals to name but a few who were exterminated in the gas chambers or worked to death. By studying and learning from the past can we help avoid these situations again. However in this climate I sometimes wonder if anything has been learnt.
In Autumn 1943, the camp administration was reorganized following a corruption scandal. By the end of 1943, the prisoner population of Auschwitz main camp, Birkenau, Monowitz and other sub-camps was over 80,000: 18,437 in the main camp, 49,114 in Birkenau, and 13,288 at Monowitz where I G Farben had its synthetic rubber plant. Up to 50,000 prisoners were scattered around 51 sub-camps such as Rajsko, an experimental agricultural station, and Gleiwitz, a coal mine (see The List of the Camps for a complete list of those sub-camps).
Initially, Schindler was mostly interested in the money-making potential of the business and hired Jews because they were cheaper than Poles—the wages were set by the occupying Nazi regime.[38] Later he began shielding his workers without regard for cost.[39] The status of his factory as a business essential to the war effort became a decisive factor enabling him to help his Jewish workers. Whenever Schindlerjuden (Schindler Jews) were threatened with deportation, he claimed exemptions for them. He claimed wives, children, and even people with disabilities were necessary mechanics and metalworkers.[39] On one occasion, the Gestapo came to Schindler demanding that he hand over a family that possessed forged identity papers. "Three hours after they walked in," Schindler said, "two drunk Gestapo men reeled out of my office without their prisoners and without the incriminating documents they had demanded."[40]