Wiemann joined the Nazi Party on 19 April 1933, with membership number 2774877. He became a member of the
Sturmabteilung (SA) in Hettstedt (Gruppe Mitte) in the same year at the rank of
Rottenführer (Section Leader); in 1934 he was promoted to
Scharführer (Squad Leader). He left the SA in 1935 after a reorganisation; SA members 45 years and above (Wiemann was 47) were reassigned to local militias. Wiemann began his career as an NSDAP
political officer after he had moved to Eilenburg (
Gau Halle-Merseburg) in March 1935. He arrived as the
Rektor (Headmaster) of a school at which the
Ortsgruppenleiter (Local Group Leader) in the Sorbenburg District, Weitze, was one of the teachers. Wiemann was initially appointed as a
Zellenleiter (Cell Leader), usually the highest Nazi official that the general population would have direct dealings with on a day-to-day basis. In 1938, Wiemann was promoted to the rank of
Amtsleiter (Office Leader), second in command to the
Ortsgruppenleiter. His main role was to act as the
Propagandaleiter (Propaganda Leader) for the area. His duties included writing political placards, sending out Party communications to
Zellenleiters in the district, and organising political events, including musical concerts. He sometimes acted as the Ortsgruppe's flagbearer. In 1939, with the reorganisation of NSDAP ranks, he became a
Haupteinsatzleiter (Head Action Leader), though continued to use the
Amtsleiter designation. In 1943, Wiemann received the
Nazi Party Long Service Award in bronze and the
Golden Party Badge (Golden Honor Award) for meritorious service to the Party, as well as the
Social Welfare Decoration for improving the welfare of the civilian population. Wiemann was also a member of a number of other NSDAP organisations. He joined the
Nationalsozialistische Lehrerbund, NSLB (
National Socialist Teachers League) on 1 April 1933 with membership number 32408. He rose to become its section treasurer from 1938 until 1941. He was also in the
Reichsluftschutzbund (State Air Protection Corps) from 1933 until 1945 and the
Nationalsozialistische Volkswohlfahrt (National Socialist People's Welfare) from 1934 until 1945. == Capture and imprisonment ==