Adolf Hitler became chancellor of Nazi Germany on January 30, 1933, and in March of that year, Heinrich Himmler announced the first concentration camp, which opened in the town of Dachau, just outside Munich, a medieval city in southern Germany.

The camp initially housed political prisoners, and its first group of detainees consisted primarily of socialists and communists. Hilmar Wäckerle, an official in the “Schutzstaffel” (a Nazi paramilitary organization commonly known as the SS), served as the first commandant of Dachau.

From the start, camp detainees were subjected to harsh treatment. On May 25, 1933, Sebastian Nefzger, a Munich schoolteacher, was beaten to death while imprisoned at Dachau. The SS administrators who operated the camp claimed that Nefzger had committed suicide, but an autopsy disclosed that he likely lost his life due to asphyxiation or strangulation.

The Munich public prosecutor summarily indicted Wäckerle and his underlings on a murder charge. The prosecutor was immediately overruled by Hitler, who issued an edict stating that Dachau and all other concentration camps were not subject to German law as it applied to German citizens. SS administrators alone would run the camps and hand out punishment as they saw fit.

That June, Theodor Eicke replaced Wäckerle as Dachau commandant. Eicke immediately released a set of regulations for the camp’s daily operation. Prisoners deemed guilty of rule breaking were to be brutally beaten. Those who plotted to escape or espoused political views were to be executed on the spot.

Prisoners would not be allowed to defend themselves or protest this treatment. Eicke’s regulations served as a blueprint for the operation of all concentration camps in Nazi Germany.

In November 1938, the prohibitive measures against German Jews that had been instituted since Hitler came to power took a violent and deadly turn during “Kristallnacht” (“Crystal Night” or “Night of Broken Glass”).

On the evening of November 9, synagogues in Germany and Austria were burned and Jewish homes, schools and businesses were vandalized. Over 30,000 Jews were arrested and dispatched to Dachau and the Buchenwald and Sachsenhausen concentration camps. Nearly 11,000 Jews ended up in Dachau.

WATCH VIDEO: The Liberators: Return to Dachau

In the fall of 1939, at the start of World War II, Dachau’s prisoners were relocated to Buchenwald and the concentration camps at Mauthausen and Flossenbuerg. For the time being, Dachau was used as a training site for members of the newly established “Waffen-SS,” an elite SS combat unit whose troops also helped run concentration camps.

By early 1940, Dachau had been reconverted into a concentration camp. Conditions at the camp were brutal and overcrowded. The facility had been designed to house some 6,000 detainees, but the population continued to rise and by 1944 approximately 30,000 prisoners were packed into the camp.

The main camp eventually expanded to include a series of subcamps, located around southern Germany and Austria, where able-bodied prisoners were used as slave labor to manufacture weapons and other materiel for Germany’s efforts in World War II.

At the dawn of World War II, Hitler came to believe that restricting the daily activities of Jews in Germany and the countries annexed by the Nazis would not resolve what he considered to be his “Jewish problem.” Nor would isolated acts of violence against Jews serve a purpose. Instead, the chancellor determined that the best solution would be the elimination of every European Jew.

Also set for extermination were members of any group considered by Hitler to be ill-equipped to reside in the new Germany. Among them were artists, intellectuals, communists, Jehovah’s Witnesses, homosexuals and others who were viewed as sexually deviant, Romani, the physically and mentally handicapped and anyone else considered to be racially or physically impure.

Between 1941 and 1944, several thousand sick and handicapped Dachau prisoners were sent to a Nazi “euthanasia” center in Hartheim, Austria, where they were put to death by exposure to lethal gas).

Several thousand Catholic clergy members were also incarcerated at Dachau. One was Titus Brandsma, a Carmelite cleric, philosopher, writer, teacher and historian as well as an avowed anti-Nazi. Brandsma arrived at Dachau in June 1942, and died the following month after being given a lethal injection.

In 1985, Brandsma was beatified by Pope John Paul II. Michał Kozal, a Polish priest, arrived at Dachau in 1941, and for two years, he attended to the spiritual needs of his fellow prisoners. In January 1943, Kozal perished from a lethal injection. Pope John Paul II beatified him in 1987.

Over the years of its operation, from 1933 to 1945, thousands of Dachau prisoners died of disease, malnutrition and overwork. Thousands more were executed for infractions of camp rules.

Starting in 1941, thousands of Soviet prisoners of war were sent to Dachau then shot to death at a nearby rifle range. In 1942, construction began at Dachau on Barrack X, a crematorium that eventually consisted of four sizeable ovens used to incinerate corpses.

With the implementation in 1942 of Hitler’s “Final Solution” to systematically eradicate all European Jews, thousands of Dachau detainees were moved to Nazi extermination camps in Poland, where they died in gas chambers.

The Nazis also used Dachau prisoners as subjects in brutal medical experiments. For example, inmates were obligated to be guinea pigs in a series of tests to determine the feasibility of reviving individuals immersed in freezing water. For hours at a time, prisoners were forcibly submerged in tanks filled with ice water. Some prisoners died during the process.

In April 1945, just prior to the liberation of Dachau by the Allied forces, the SS ordered approximately 7,000 prisoners to embark on a six-day-long death march to Tegernsee, located to the south. Those unable to maintain a steady marching pace were shot by SS guards. Other marchers died from starvation or physical exhaustion.

On April 29, 1945, the United States military entered Dachau, where they found thousands of mostly emaciated prisoners. The U.S. soldiers also discovered several dozen train cars loaded with rotting corpses. The prisoners who survived the Tegernsee death march were freed by American troops on May 2.

During the entire time in which Dachau served as a concentration camp and death camp, over 200,000 prisoners were registered as having passed through its gates. An inestimable number, running into the thousands, were never registered, making it impossible to know exactly how many people were imprisoned at Dachau and how many died there.

Following the Allied victory that marked the end of World War II, Dachau was used to house SS officers facing trial for war crimes. It was also used temporarily as a U.S. military base. Dachau was finally closed in 1960.

The Dachau Concentration Camp Memorial Site, which stands on the site of the original camp, opened to the public in 1965. It is free to enter and thousands of people visit Dachau each year to learn about what happened there and remember those who were imprisoned and died during the Holocaust.

READ MORE: The Horrifying Discovery of Dachau Concentration Camp

Dachau. United States Holocaust Memorial Museum.
The Last Days of the Dachau Concentration Camp. The National WWII Museum.
Scenes From Hell: Pfc. Harold Porter - Atrocities at Dachau Concentration Camp, 1945. The National Archives.