Eichler was born in
Berlin, the son of a postal worker. He attended
Volksschule and then became a clerk. Between 1915 and 1918, he served as a soldier in the
First World War. In 1922, he went to work as the secretary of the
socialist philosopher,
Leonard Nelson, who founded the
Internationaler Sozialistischer Kampfbund (ISK). He became a close confidant of Nelson. From 1932 to 1933, he was the
editor-in-chief of the ISK's anti-
Nazi newspaper,
Der Funke, which published an "
Urgent Call for Unity" in June 1932 calling for support of the SPD and the
KPD in the
July 1932 German federal election. It was signed by 33 well-known scientists, authors and artists, including
Albert Einstein,
Emil Julius Gumbel,
Kurt Hiller,
Erich Kästner,
Käthe Kollwitz /
Arthur Kronfeld,
Heinrich Mann,
Pietro Nenni,
Paul Oestreich,
Franz Oppenheimer,
Theodor Plivier,
Minna Specht,
Helene Stöcker,
Ernst Toller,
Erich Zeigner and
Arnold Zweig. Eichler emigrated to
France in 1933 after the
National Socialists
seized power. In
Paris, he got involved with the
Lutetia Circle, the 1935-1936 attempt of exiles to establish and support a
Volksfront against the
Third Reich. He also became publisher of the
Reinhart Briefe, which were secretly disseminated in Germany, and the
Socialistische Warte, which published articles by
Hilde Meisel. Eichler's political activities caused him to be expelled from France in 1938. Shortly before the outbreak of war, Eichler found asylum in
England, where he returned to the SPD. In London, Eichler worked at the
BBC making broadcasts aimed at German workers and published
Europe Speaks. In 1941, he was a founding member and board member of the
Union deutscher sozialistischer Organisationen in Großbritannien, which, after the war, merged with the SPD. Toward the end of his exile in
London, he worked closely with historian
Susanne Miller, a German Jewish refugee, who later became his wife. ==Postwar==