He joined the German Metal Workers ' Union in 1923 , later becoming a member of the Revolutionary Trades Union Opposition ( RGO / '' Revolutionäre Gewerkschafts Opposition '' ) movement . In 1931 Hofmann joined the Communist Party ( KPD / '' Kommunistische Partei Deutschlands '' ) . In March 1931 he set off from Kiel in a kayak and succeeded in getting himself via Denmark , Sweden and Finland to Kronstadt , the principal port adjacent to Leningrad ( as it was then called ) . He also succeeded in obtaining a residence permit in the Soviet Union . He stayed in the country for many years , resuming his work as a machinist and later in 1933 moving on to the Urals region where he became a foreman in a heavy machinery plant in Nadeschinsk ( in 1939 renamed Serov ) . He moved again , in 1933 , to Swerdlowsk taking another job in production management at a heavy machinery plant , remaining here till 1937 . In 1938 he was working as an assembly shop foreman at the iron and steel complex at Tagilstroyevsky in the northern part of Nizhny Tagil . However , he was then targeted in one of the Stalinist purges : he was arrested in February 1938 and taken to Moscow where he spent eleven months in custody . He was released on 15 January 1939 and readmitted to the Communist Party
Stalinist purges
Great Purge
Artur Hofmann