In 1927 Backe was inspector and administrator on a big farm in Pommern. In 1928 he was married to Ursula. With financial support of his father-in-law, in November 1928 he became tenant of domain Hornsen, with around 950 acres in the district of Alfeld. He proceeded to lead the farm successfully. Finally, he joined the SS in October 1933. He undertook various duties in the administration of Nazi Germany, succeeding Richard Walther Darré as Minister of Food in May 1942 and becoming Minister of Agriculture in April 1944. Backe was a prominent member of the younger generation of Nazi technocrats who occupied second-tier administrative positions in the Nazi system such as Reinhard Heydrich, Werner Best, and Wilhelm Stuckart. Like Stuckart, who held the real power in the Interior Ministry (officially led by Wilhelm Frick) and Wilhelm Ohnesorge in the Reichspostministry (officially led by the conservative Paul Freiherr von Eltz-Rübenach), Backe was the "de facto" Minister of Agriculture under Darré, even before his promotion to that post.