Marx and Engels archive taken out of Germany in 1933 and bought by Posthumus

The Social Democratic Party of Germany once assembled an impressive archive of Karl Marx and Friedrich Engels, comprising the extensive correspondence between Marx and Engels, other letters, and their manuscripts and notes. In 1933 the Russian historian Boris Ivanovich Nikolaevsky managed to get the party's archive out of Germany. The party's property was being confiscated, and this was the only way to save the most valuable collection of documents. The inevitable decision was taken to sell the archive.

The first to declare a wish to acquire so important a collection was the Marx-Engels-Lenin Institute in Moscow, and behind its decision, of course, stood Stalin in person, who had been gathering in Moscow for years every document connected with the birth of Bolshevik and Marxist ideology. The Soviet institute offered a colossal sum, but the party leadership, for political reasons, judged it a disgrace even to contemplate selling its most precious possession to the USSR.

In the end the archive was bought by Nicolaas Wilhelm Posthumus, professor of economic history at the Netherlands School of Commerce. Posthumus was a passionate collector of the archives of trade unions and socialist parties, and he founded in Amsterdam the International Institute of Social History, which exists to this day and whose declared aim was the rescue of the historical heritage of the working class.

Besides the archive of Marx and Engels, the holdings of Posthumus's institute included the manuscript of the Manifesto of the Communist Party, signed by Karl Marx, handwritten pages of Capital, the minutes of a session of the General Council of the First International in 1864, and the archives of numerous socialist organisations and public institutions from all over Europe.

Among the treasures of the IISH, which German reports called "the intellectual centre of the Marxist struggle against fascism", were several valuable collections of Russian émigrés, including the papers of Leon Trotsky, donated to the Paris branch of the institute in 1936 by his son Lev Sedov. Incidentally, that branch was headed by the very same Boris Nikolaevsky, and the institute's collection grew largely thanks to his personal connections with the Russian emigration.

This part of the archive was also of keen interest to the Soviet leadership, which, taught by the failed attempt to buy the SPD archive, this time resorted to less civilised methods. In 1936 agents of Stalin's security service, the GPU, stole Trotsky's most valuable archival documents from the Paris branch of the IISH and were such