The first buildings in the Dachau concentration camp complex consisted of the remnants of an old WWI munitions factory that was located in the northeastern portion of the town. These buildings, with a capacity of about 5,000 prisoners, served as the main camp structures until 1937, when prisoners were forced to expand the camp and demolish the original buildings.

But Auschwitz-Birkenau became more than a concentration camp. In the spring of 1942 gas chambers were built at Birkenau and mass transports of Jews began to arrive. Some of the new arrivals were inducted into the camp as registered prisoners, but the great majority were gassed immediately. These gassing operations were greatly expanded in the spring of 1943 with the construction of four purpose-built gas chamber and crematorium complexes, which included such refinements as electric lifts to carry bodies up to the crematoria. Each crematorium could handle 2,000 victims daily. In a nearby group of barracks, nicknamed 'Canada' by the prisoners, victims' belongings were sorted for transportation to the Reich. The victims' hair was used to stuff mattresses; gold teeth were melted down and the gold deposited to an SS account.

Dachau was the concentration camp that was in operation the longest from March 1933 to April 1945, nearly all twelve years of the Nazi regime. Dachau's close proximity to Munich, where Hitler came to power and where the Nazi Party had its official headquarters, made Dachau a convenient location. From 1933 to 1938, the prisoners were mainly German nationals detained for political reasons. After the Reichspogromnacht or Kristallnacht, 30,000 male Jewish citizens were deported to concentration camps. More than 10,000 of them were interned in Dachau alone. As the German military occupied other European states, citizens from across Europe were sent to concentration camps. Subsequently, the camp was used for prisoners of all sorts, from every nation occupied by the forces of the Third Reich.[15]:137
Gun did not explain how these 300 prisoners died on the night of the liberation of the camp, but he did write that the prisoners had weapons and that the International Committee of Dachau had made sure that the prisoners who had cooperated with the German guards were not allowed to escape. Others may have died from eating too much of the canned food and chocolate given to them by the Americans, and undoubtedly there were deaths among the 900 prisoners sick with typhus in the infirmary.
^ Jump up to: a b Dan Stone (Histories of the Holocaust, 2010): "Europe's Romany (Gypsy) population was also the victim of genocide under the Nazis. Many other population groups, notably Poles, Ukrainians, and Soviet prisoners of war were killed in huge numbers, and smaller groups such as Jehovah's Witnesses, Black Germans, and homosexuals suffered terribly under Nazi rule. The evidence suggests that the Slav nations of Europe were also destined, had Germany won the war, to become victims of systematic mass murder; and even the terrible brutality of the occupation in eastern Europe, especially in Poland, can be understood as genocidal according to the definition put forward by Raphael Lemkin in his major study, Axis Rule in Occupied Europe (1944), the book that introduced the term 'genocide' to our vocabulary. Part of the reason for today's understanding, though, is a correct assessment of the fact that for the Nazis the Jews were regarded in a kind of 'metaphysical' way; they were not just considered as racially inferior (like Romanies), deviants (like homosexuals) or enemy nationals standing in the way of German colonial expression (like Slavs). ... [T]he Jews were to some extent outside of the racial scheme as defined by racial philosophers and anthropologists. They were not mere Untermenschen (sub-humans) ... but were regarded as a Gegenrasse: "a 'counter-race', that is to say, not really human at all. ... 'Holocaust', then, refers to the genocide of the Jews, which by no means excludes an understanding that other groups—notably Romanies and Slavs—were victims of genocide. Indeed ... the murder of the Jews, although a project in its own right, cannot be properly historically situated without understanding the 'Nazi empire' with its grandiose demographic plans."[32]
Shortly after the outbreak of war in September 1939, thirty-one-year-old Schindler showed up in occupied Krakow. The ancient city, home to some 60,000 Jews and seat of the German occupation administration, the Generalgouvernement, proved highly attractive to German entrepreneurs, hoping to capitalize on the misfortunes of the subjugated country and make a fortune. Naturally cunning and none too scrupulous, Schindler appeared at first to thrive in these surroundings.  In October 1939, he took over a run-down enamelware factory that had previously belonged to a Jew.  He cleverly maneuvered his steps- acting upon the shrewd commercial advice of a Polish-Jewish accountant, Isaak Stern - and began to build himself a fortune. The small concern in Zablocie outside Krakow, which started producing kitchenware for the German army, began to grow by leaps and bounds. After only three months it already had a task-force of some 250 Polish workers, among them seven Jews. By the end of 1942, it had expanded into a mammoth enamel and ammunitions production plant, occupying some 45,000 square meters and employing almost 800 men and women. Of these, 370 were Jews from the Krakow ghetto, which the Germans had established after they entered the city.
German students over the age of 12 are required to tour a concentration camp as part of the on-going education of the present generation of German citizens in the evil perpetrated by the Nazi regime over 60 years ago. German soldiers are also required to tour the former concentration camps. Most visitors associate Dachau with the death of 6 million Jews in the Holocaust, although the majority of the inmates at Dachau were Catholics.
The Holocaust was the systematic, bureaucratic, state-sponsored persecution and murder of six million Jews by the Nazi regime and its collaborators. Holocaust is a word of Greek origin meaning "sacrifice by fire." The Nazis, who came to power in Germany in January 1933, believed that Germans were "racially superior" and that the Jews, deemed "inferior," were an alien threat to the so-called German racial community.
Jewish prisoners were concentrated at Bergen-Belsen, hitherto not known as one of the worst camps; but in the chaotic final months of the war conditions were allowed to deteriorate catastrophically. When British troops came across the camp on 15 April 1945, they encountered 10,000 unburied corpses, a raging typhus epidemic and 60,000 sick and dying prisoners crammed into overcrowded barracks without food or water.
Last week the jubilance of impending victory was sobered by the grim facts of the atrocities which the Allied troops were uncovering all over Germany. For 12 years since the Nazis seized power, American have heard charges of German brutality. Made skeptical by World War I "atrocity propaganda," many people refused to put much faith in stories about the inhuman Nazi treatment of prisoners.

The camp was liberated on April 15, 1945, by the British 11th Armoured Division.[4] The soldiers discovered approximately 60,000 prisoners inside, most of them half-starved and seriously ill,[5] and another 13,000 corpses, including those of Anne and Margot Frank, lying around the camp unburied.[4] The horrors of the camp, documented on film and in pictures, made the name "Belsen" emblematic of Nazi crimes in general for public opinion in many countries in the immediate post-1945 period. Today, there is a memorial with an exhibition hall at the site.