Etta Federn-Kohlhaas (April 28, 1883 – May 9, 1951) or Marietta Federn, also published as Etta Federn-Kirmsse and Esperanza, was a writer, translator, educator and important woman of letters in pre-war Germany. In the 1920s and 1930s, she was active in the Anarcho-Syndicalism movement in Germany and Spain.
Raised in Vienna, she moved in 1905 to Berlin, where she became a literary critic, translator, novelist and biographer. In 1932, as the Nazis rose to power, she moved to Barcelona, where she joined the anarchist-feminist group Mujeres Libres, (Free Women), becoming a writer and educator for the movement. In 1938, toward the end of the Spanish Civil War, she fled to France. There, hunted by the Gestapo as a Jew and a supporter of the French Resistance, she survived World War II in hiding.
In Germany, she published 23 books, among them translations from the Danish, Russian, Bengali, Ancient Greek, Yiddish and English. She also published two books while living in Spain.
The story of Etta Federn and her two sons inspired the 1948 play Skuggan av Mart  (Marty's Shadow), by the important Swedish writer Stig Dagerman, who published novels, plays and journalism before committing suicide at age 31. The play based on Federn was first performed at the Royal Dramatic Theatre in Stockholm, and has since played in several countries, including Ireland, the Netherlands, Cyprus and France. Marty's Shadow was first performed in the U.S. in 2017, by the August Strindberg Repertory Theatre in New York City.
Raised in an assimilated Jewish family in Vienna, Etta Federn was the daughter of suffragist Ernestine (Spitzer) and Dr. Salomon Federn, a prominent physician and pioneer in the monitoring of blood pressure.
Her brother Paul Federn, a psychoanalyst, was an early follower and associate of Sigmund Freud. An expert on ego psychology and the treatment of psychosis, he served as vice president of the Vienna Psychoanalytic Society.
Her brother Walther Federn was an important economic journalist in Austria before Hitler came to power. Her brother Karl Federn was a lawyer who, after fleeing to the UK, became known for his anti-Marxist writings.
Her sister Else Federn was a social worker in Vienna, active in the Settlement Movement. A park in Vienna was named for her in 2013.
Etta Federn's first husband was Max Bruno Kirmsse, a German teacher of children with mental disabilities. Her second husband was Peter Paul Kohlhaas, an illustrator. She had two sons, Hans and Michael, one from each marriage. Her older son, known as Capitaine Jean in the French Resistance, was murdered by French collaborators in 1944.
In Vienna and Berlin, Etta Federn studied literary history, German philology and Ancient Greek. She worked in many genres, publishing articles, biographies, literary studies and poetry. She also wrote a novel that remained unpublished.
As a journalist, she was a literary critic for the Berliner Tageblatt. She wrote biographies of Dante Alighieri and Christiane Vulpius (wife of Goethe). In 1927, she published a biography of Walther Rathenau, the liberal Jewish Foreign Minister of Germany, who had been assassinated in 1922 by anti-Semitic right-wing terrorists. This book made her the target of Nazi death threats.
During the 1920s, Federn became part of a circle of anarchists, including Rudolf Rocker, Mollie Steimer, Senya Fleshin, Emma Goldman, and Milly Witkop Rocker, who would become her close friend. She contributed to various anarchist newspapers and journals related to the Free Workers' Union of Germany.
In Berlin, Federn also encountered several Polish-born Jewish poets who wrote in Yiddish. In 1931, her translation of the poetry collection Fischerdorf (Fishing Village) by Abraham Nahum Stencl was reviewed favorably by Thomas Mann, who admired Stencl's "passionate poetic emotion."
In 1932, she left Berlin, realizing that under the Nazis she would no longer be able to publish her writings. She moved with her sons to Barcelona, Spain, where she joined the anarchist movement Mujeres Libres (Free Women), which provided such services as maternity centers, day-care centers, and literacy training to women. She learned Spanish and became director of four progressive schools in the city of Blanes, educating both teachers and children in secular values and antimilitarism. Starting in 1936, she also published a number of articles in the movement's women-run magazine, also called Mujeres Libres.
Like many anarchist women, she believed in the importance of literacy for women, in birth control and sexual freedom, and in the power of educated women to be good mothers. She wrote: "Educated mothers relate their own experiences and sufferings to their children; they intuitively understand their feelings and expressions. They are good educators, as they are also friends of the children they educate."
In 1938, as Francisco Franco's fascists bombed Barcelona and defeated the left, Federn fled to France, where she was held in internment camps as a foreign refugee. She spent the war in hiding in Lyon, at times in a monastery, and did translation work for the French Resistance. She spent her final years in Paris, supported in part by her relatives in the USA. Because her son was killed as a Resistance fighter, she was awarded French citizenship.
- Christiane von Goethe: ein Beitrag zur Psychologie Goethes (Christiane von Goethe: A Contribution to Goethe's Psychology), 1916.
- Dante: ein Erlebnis für werdende Menschen (Dante: An Experience for the Expectant), 1923.
- Walther Rathenau: sein Leben und Wirken (Walter Rathenau: His Life and Work), 1927.
- Mujeres de la Revoluciones (Revolutionary Women), 1937. Reissued in German as Etta Federn: Revolutionär auf ihre Art, Von Angelica Balabanoff bis Madame Roland, 12 Skizzen unkonventioneller Frauen (Etta Federn: Revolutionary in her Way: From Angelica Balabanoff to Madame Roland, 12 Sketches of Unconventional Women), edited and translated by Marianne Kröger, 1997.
- H.C. Andersens Märchen, Tales of Hans Christian Andersen, translated from the Danish, 1923. Reissued 1952.
- Shakespeare-Lieder, Sonnets of William Shakespeare, translated from the English, 1925.
- Wege der liebe : drei Erzählungen (The Ways of Love: Three Stories), by Alexandra Kollontai, translated from the Russian, 1925. Reissued 1982.
- Gesichte, Poems of Samuel Lewin, translated from the Yiddish, 1928.
- Fischerdorf (Fishing Village), Poems of A. N. Stencl, translated from the Yiddish, 1931.
- Sturm der Revolution (The Storm of Revolution), Poems of Soumyendranath Tagore, translated from the Bengali, 1931.
- Anakreon, Poems of Anacreon, translated from the Ancient Greek, 1935.