Winkelmann passed the state examination in 1913 at the
University of Kiel, and on 26 September 1914 he received his licence to practise as a
doctor. He received his
doctorate from Walter Stoeckel, worked at various hospitals and was employed as a doctor in the
Imperial German Navy during the First World War. After the war he was in 1918 a member of a volunteer corps, before settling as a practising
physician in
Lippstadt. On 1 May 1933 he joined the
NSDAP (membership No. 3.101.530), and on 18 June 1933 he joined the
Schutzstaffel (SS No. 109.112). Winkelmann was promoted to SS
Untersturmführer on 15 September 1935, to SS
Obersturmführer on 9 November 1936 and to SS
Hauptsturmführer on 30 January 1939. From January to October 1940 he was employed as a regimental doctor with the rank of SS Hauptsturmführer in the 8th SS regiment of the
Waffen SS in
Kraków. Until 1 December 1944, he worked as a medical officer in
Częstochowa. After brief assignments at the
Groß-Rosen and
Sachsenhausen concentration camps, he was transferred to the
Ravensbrück concentration camp at the end of February 1945. == Ravensbrück ==