Charged with sedition, she was eventually deported to Soviet Russia, where she met her lifelong partner Senya Fleshin and agitated for the rights of anarchist political prisoners in the country.

For her activities, she and Fleshin were again deported to western Europe, where they spent time organising aid for exiles and political prisoners, and took part in the debates of the international anarchist movement.

[3] Together with other Jewish anarchists, Steimer helped form a clandestine collective called Der Shturm ("The Storm"), which published radical works in the Yiddish language.

Following some internal conflict, in January 1918, the group reorganized and launched a new monthly journal titled Frayhayt ("Freedom"),[4] which published articles by Jewish radicals such as Georg Brandes and Maria Goldsmith.

[9] By the summer of 1918, the group had drawn the attention of the authorities after they had begun distributing leaflets denouncing the allied intervention in the Russian Civil War and calling for a social revolution in the United States by means of a general strike.

[15] With support from both radicals and liberals, notably including Zechariah Chafee and other legal scholars of Harvard University,[16] the sentence was appealed and the defendants were released on bail.

[18] On March 11, 1919, during a police raid against the Russian People's House on New York's East 15th Street, Steimer was arrested on charges of incitement and subsequently transferred to Ellis Island.

When the Supreme Court upheld her conviction, her co-defendants informed her of a plan to flee the country into exile, but Steimer herself refused to cooperate, as she did not want to dishonor the workers who had paid her $40,000 in bail (equivalent to $725,000 in 2024).

[32] Emma Goldman had left for exile,[33] Peter Kropotkin had died of old age and both the Kronstadt rebellion and the Makhnovist movement had been suppressed by the Red Army, while hundreds more anarchists were still held in the prisons of the Cheka.

[32] Despite the climate of political repression, Steimer made a new home in Petrograd, where she met and fell in love with Senya Fleshin, a veteran of the Makhnovist movement.

[36] When ACLU founder Roger Nash Baldwin received news of Steimer's treatment, he declared himself "moved humanly to condemn both governments involved [the United States and Soviet Union] and to give her such aid as I can.

From the German capital, Steimer wrote articles about her experiences in Russia for the British anarchist newspaper Freedom, to which she denounced the authoritarianism of the Communist Party.

[40] During this period, Steimer also met a number of other anarchists, including Harry Kelly, Rose Pesotta, Rudolf Rocker and Milly Witkop, and was briefly reunited with her co-defendants Jack and Mary Abrams, who had also left Russia out of disillusionment with the Revolution.

[45] In Mexico City, the couple operated a photographic studio, became close with a group of Spanish anarchist exiles and were once again reunited with Jack and Mary Abrams.