Sprenger was born in Oberhausen near Bad Bergzabern in the Palatinate. In 1922, the postal inspector Sprenger became a member of the Nazi Party. Sprenger was a militant anti-Semite and rose quickly through the ranks, first to Gauleiter of Hesse-Nassau-South in 1927, and by September 1930 to member of the Reichstag.
On 5 May 1933 Sprenger was appointed Reichsstatthalter of Hesse and leader (Gauleiter) of the new Gau formed from the Prussian province of Hesse-Nassau, which included the federated state of Hesse-Darmstadt. In the process of the Gleichschaltung, in particular due to the ‘Reichsstatthaltergesetz’ of 30 January 1935, he was able to take over leadership of the provincial government from Philipp Wilhelm Jung. Besides Martin Mutschmann of Saxony, he was the only governor charged with such a double function.
On 1 September 1939, SA-Obergruppenführer Sprenger became Reich Commissar of Defense District XII, and as of 1 December 1943 also in the Gau of Hesse-Nassau. Later Sprenger was appointed High President (Oberpräsident) of the Prussian province of Nassau in 1944, after Prince Philip of Hesse-Kassel had been removed. On the night of 25 to 26 March 1945, Sprenger fled from the advancing U.S. Army from Frankfurt to Kössen, Austria, where he and his wife committed suicide on 7 May 1945.