Back to Berlin he joined the German Democratic Party (DDP) in 1920 and in 1921 became district administrator (Landrat) at Rosenberg, Marienwerder (today Susz, Poland).

As a supporter of the Weimar Coalition's Reichsbanner Schwarz-Rot-Gold paramilitary group his times in office were marked by fierce conflicts with the rising forces of the Communists and the Nazi Party.

Friedensburg continued to hold great power in the Soviet occupation zone as chairman of the eastern sector of the CDU and the German Central Fuel Industry Administration.

When Ulbricht and Gustav Sobottka began plotting to oust him and accused him to the NKVD of maintaining contacts with former Nazis, he fled to West Berlin.

[1] After the Soviet blockade of the western sectors had begun on 24 June 1948, Schroeder fell seriously ill and had to proceed to Hamburg for medical treatment.