10 Most-Evil Nazis You’ve Never Even Heard Of

10. Friedrich Jeckeln - Developed The "Jeckeln System" For Murdering "Undesirables"

An SS-Obergruppenführer (a rank second only to Heinrich Himmler in the SS), Friedrich Jeckeln (pictured above, far left, standing up) led one of the largest Einsatzgruppen - "task forces" or "deployment groups" responsible for mass killings - during the German occupation of the Soviet Union. Jeckeln was responsible for ordering the slaughter of more than 100,000 Jews, Slavs, Roma and other "undesirables" in the conquered territories during World War II.

Having joined the Nazi Party as early as October 1929, Jeckeln became an SS member a year later, before being elected as a member of the Reichstag in 1932. Known as being ruthless, hard and brutal, Jeckeln murdered members of opposition parties - particularly those on the far left.

Developing his own extremely efficient method for killing large numbers of people at once - known as the "Jeckeln System", where victims' mass graves were already dug before they were stripped, forced to lie flat in the pits and then executed - Jeckeln organised three infamous Nazi massacres of World War II: Rumbala (November and December 1941, where 25,000 were murdered), Babi Yar (September 1941 onwards, when more than 180,000 were murdered), and Kamianets-Podilskyi (June 1941, where at least 24,000 Jews were murdered). Jeckeln was even awarded the "War Merit Cross with Swords" (or "Kriegsverdienstkreuz") for the massacre at Rumbula, and he was eventually captured by Soviet troops near Halbe in north-east Germany on April 28, 1945.

Tried before a Soviet military court in Riga, Latvia, in early-1946, Jeckeln was calm and admitted his guilt, explaining:

"I have to take full responsibility for what happened in the borders of Ostland, within SS, SD and the Gestapo. Thereby increases much my fault. "My fate is in the hands of the High Court, and so I ask only to pay attention to mitigating circumstances. I will accept a sentence in full repentance and I will consider as worthy punishment."

Found guilty of war crimes, he was hanged in Victory Square in Riga on February 3, 1946.