In the Autumn of 1918 Frida Rubiner visited Vienna: her motives, according to her own reports, were more artistic than political, and she probably returned to Zürich before the end of the year. Some (though not all) sources indicate that one or both of the Rubiners were expelled from Switzerland at the end of 1918. In February 1919 they returned to Berlin, and while Ludwig Rubiner took a job with a publishing house, his wife embarked on a trip to Kaunas and Vilnius to visit relatives in the war torn former western territories of the Russian empire. She (probably) participated - possibly without any "official mandate" - in the founding congress of the Communist International (Comintern) which took place in Moscow early in March 1919. She had certainly been an early member - some sources say one of the (many) co-founders earlier that year - of the Communist Party of Germany.