Otto Winkelmann was a German police official, SS-Obergruppenführer and General of the Waffen-SS who served as the Higher SS and Police Leader (HSSPF) in Hungary during the deportation and extermination of Hungarian Jews.

Obergruppenführer was a paramilitary rank in Nazi Germany that was first created in 1932 as a rank of the Sturmabteilung (SA) and adopted by the Schutzstaffel (SS) one year later. Until April 1942, it was the highest commissioned SS rank after only Reichsführer-SS. Translated as "senior group leader", the rank of Obergruppenführer was senior to Gruppenführer. A similarly named rank of Untergruppenführer existed in the SA from 1929 to 1930 and as a title until 1933. In April 1942, the new rank of SS-Oberst-Gruppenführer was created which was above Obergruppenführer and below Reichsführer-SS.