His father was the Menshevik leader Rafail Abramovich (Rein). Mark Rafailovich Rein was born in 1909 in Vilnius, Lithuania (then Vilna in the Russian empire). His father was a prominent leader of the Menshevik faction of the Russian Social-Democratic Workers" Party (Russian Social-Democratic Workers’ Party).
He lived mostly in Berlin and Paris. In 1932 he graduated from the Berlin Polytechnic. In 1936 he went to Spain to support the Republican, anti-fascist forces during the Spanish Civil War.
Inter alia, he became a friend to Willy Brandt there, whom he met in Barcelona.
On April 9, 1937, he was kidnapped in Barcelona by agents of the Soviet secret service Joint State Political Administration. He was spirited to Russia, apparently with the intention of using him in the show trial of Alexey Rykov and Nikolai Bukharin. He was supposed to connect the accused in the third Moscow Trial in 1938 to the exiled Menshevik leadership.
He worked as a journalist for several socialist papers. In spite of frantic efforts by Rafail Abramovich and western socialist supporters, he was never seen alive again and is thought to have been murdered by the Joint State Political Administration.
As a young man he became a member of the Menshevik Russian Social-Democratic Workers’ Party, the German Social Democratic Party and the Swedish Social Democratic Party.
He was more sympathetic to the Soviet Union than his father, and for a while supported the idea of a unification of social-democratic and communist parties.
