Johann Niemann was an SS-Untersturmführer

Untersturmführer

Untersturmführer was a paramilitary rank of the German Schutzstaffel first created in July 1934. The rank can trace its origins to the older SA rank of Sturmführer which had existed since the founding of the SA in 1921...

(Second Lieutenant) and deputy commandant of Sobibor extermination camp

Sobibór extermination camp

Sobibor was a Nazi German extermination camp located on the outskirts of the town of Sobibór, Lublin Voivodeship of occupied Poland as part of Operation Reinhard; the official German name was SS-Sonderkommando Sobibor...

. Niemann directly perpetrated the genocide

Genocide

Genocide is defined as "the deliberate and systematic destruction, in whole or in part, of an ethnic, racial, religious, or national group", though what constitutes enough of a "part" to qualify as genocide has been subject to much debate by legal scholars...

 of Jews

Jews

The Jews , also known as the Jewish people, are a nation and ethnoreligious group originating in the Israelites or Hebrews of the Ancient Near East. The Jewish ethnicity, nationality, and religion are strongly interrelated, as Judaism is the traditional faith of the Jewish nation...

 and other peoples at Sobibor during the Operation Reinhard

Operation Reinhard

Operation Reinhard was the code name given to the Nazi plan to murder Polish Jews in the General Government, and marked the most deadly phase of the Holocaust, the use of extermination camps...

 phase of The Holocaust

The Holocaust

The Holocaust , also known as the Shoah , was the genocide of approximately six million European Jews and millions of others during World War II, a programme of systematic state-sponsored murder by Nazi...

.

Niemann joined the Nazi Party in 1931 as member number 753,836 and the SS in 1934 as member number 270,600.

Niemann first served at Bełżec extermination camp, at the rank of SS-Oberscharführer (Staff Sergeant), where he commanded Camp II, the extermination area. He then was transferred to Sobibor extermination camp

Sobibór extermination camp

Sobibor was a Nazi German extermination camp located on the outskirts of the town of Sobibór, Lublin Voivodeship of occupied Poland as part of Operation Reinhard; the official German name was SS-Sonderkommando Sobibor...

. Niemann was deputy commander of Sobibor on various occasions in 1942 before being given the position permanently in early 1943. After Heinrich Himmler

Heinrich Himmler

Heinrich Luitpold Himmler was Reichsführer of the SS, a military commander, and a leading member of the Nazi Party. As Chief of the German Police and the Minister of the Interior from 1943, Himmler oversaw all internal and external police and security forces, including the Gestapo...

's visit to Sobibor on 12 February 1943, Niemann was promoted to SS-Untersturmführer.

Karl Frenzel

Karl Frenzel

SS-Oberscharführer Karl August Wilhelm Frenzel was the commandant of Sobibor extermination camp's Lager I section, which was the section for the Sonderkommando forced-labor prisoner-workers, who also herded victims into the gas chambers...

, also a commandant at Sobibor

Sobibór

Sobibór is a village in the administrative district of Gmina Włodawa, within Włodawa County, Lublin Voivodeship, in eastern Poland. It lies close to the Bug River, which forms the border with Belarus and Ukraine. Sobibór is approximately south-east of Włodawa and east of the regional capital...

, recalled how Niemann handled a particular threat of prisoner revolt within the camp:
On 14 October 1943, a prisoner uprising took place throughout the Sobibor camp. Niemann was the highest-ranking SS officer who was on duty at the camp that day, and so he was the first person targeted to be assassinated by the prisoners. Johann Niemann was killed in the tailor's barracks with an axe to his head by Alexander Shubayev, a Jewish Belorussian Red Army soldier who had been imprisoned at Sobibor as a prisoner of war.