After finishing at her single-sex secondary school she came into contact with the circle of Berlin-based expressionist poets around Georg Heym, Else Lasker-Schüler and, most notably, Franz Pfemfert.
[1] During the revolutionary period that followed the war she was contributing to the journal Russische Korrespondenz, and she was also working as a secretary for the Communist Workers' Party, a breakaway grouping founded in April 1920 by Franz Jung[5] (together with Alexander Schröder, Alexander Schwab and Bernhard Reichenbach) as part of the bewildering political splintering that was a feature of left-wing politics in Germany at the time.
Jung was banned from overseas travel, but nevertheless Franz and Cläre managed to cross into Denmark at the end of August 1921, and then obtained a passage to the Soviet Union on a freight steamer called "Flora":[5] the two of them now settled in Moscow.
[1] She later worked, along with Franz Jung, on the rebuilding of the "Ressora" metalwork plant in Petrograd[1] which, by the time circumstances had persuaded them to leave the country in November 1923, was back to producing steel oil barrels and ship building components.
[1] In 1927, together with Franz, Cläre took a position with Deutscher Feuilleton Dienst, for which she would still be working, despite the intervening personal and political turmoil, till 1944.
From 1933 Cläre Jung was combining her publishing work with (now illegal) anti-Nazi activism, working with Harro Schulze-Boysen and others to help Jewish and political victims of government oppression, and producing press releases on behalf of non-Nazi, and therefore illegal, news services (so called "Green reports" / "Grüne Berichte").
It is clear from subsequent correspondence after 1944 when Franz's daughter (by an earlier marriage) died, that the two did not entirely lose contact following the divorce however.
[1] She left the ballet school position in 1955, now working as a freelance writer, making contributions to East German newspapers and magazines.