The Gestapo was the Geheime Staatspolizei or the secret police of Nazi Germany and would become a part of the SS.
Originally the Gestapo was established in 1933 on April 26 and made up of the Prussian Secret Police.
Their first commander was Gestapo agent Rudolf Deils who ran the Gestapo not unlike the FBI, it was not until Hermann Göring took over as commander that things changed. They changed in a way that the citizens learned to fear them, if detained they were tortured and held without formal charges, however they were made to sign a paper stating that they had asked to be confined in the Gestapo prison.