Short answers, pulled from the story.
The first Nazi concentration camp was established on the 3rd of March 1933 in Nohra. This facility operated as a school before the Nazi regime seized power and was created just three days after Adolf Hitler assumed the chancellorship of Germany.
Heinrich Himmler appointed Theodor Eicke as the second commandant of Dachau on the 26th of June 1933. Eicke subsequently drafted the Disciplinary and Penal Code and became the first inspector of the Concentration Camps Inspectorate in December 1934.
New purpose-built camps opened during this period included Sachsenhausen in September 1936, Buchenwald in July 1937, Flossenbürg in May 1938, Mauthausen in August 1938, and Ravensbrück in May 1939. Ravensbrück was the first purpose-built camp specifically for female prisoners.
The high command of the SS ordered the murder of ill and exhausted prisoners in April 1941, with at least 6,000 and potentially as many as 20,000 people killed by April 1942. Selected Soviet prisoners of war were also killed within the concentration camps beginning in August 1941.
By the end of the war, only 5 to 10 percent of the camp population were Reich Germans from Germany or Austria. The majority of prisoners were people from countries occupied by the Wehrmacht, including more than 100,000 Soviet prisoners of war.
Major evacuations of the camps occurred in mid-1944 from the Baltics and eastern Poland, January 1945 from western Poland and Silesia, and in March 1945 from concentration camps in Germany. These death marches were deliberately ordered by Himmler to keep prisoners under Nazi control.