From 1918 to 1933, Schäffer was a member of the BVP. In 1929, he became chairman of this Bavarian regionalist party. From 1920 to 1933, he was a member of the Landtag of Bavaria. In his early political career, he made some anti-Semitic speeches, a fact that would haunt him in his later political life. Nevertheless, he opposed the Nazis' rise to power in Bavaria and took part in the formation of the "Bayernwacht" in 1931, an organisation aimed at protecting conservative politicians from the SA. He aimed at forming a coalition, which would include the Nazi Party and the Centre Party, arguing that such a step would neutralise the Nazi party to some extent. After this failed, he attempted to elevate the last Bavarian crown prince, Rupprecht, to the dictatorial position of "Staatskommissar". The move ultimately failed due to the resistance of Bavarian prime minister, Heinrich Held, who feared that Schäffer would be made prime minister in his stead.