Based on historical event - the assassination of Leon Trotsky in 1940.
A world with fewer priests and more justice. And that's a world worth dying for.
In the NKVD training center dining hall where Mercader talks to the high officers, there is a banner over the internal passage arch. It's a standard multiplication of "Proletarians Of The World, Unite" from the Karl Marx's Manifesto, translated to native languages of every Soviet Republic. One clearly visible is in Estonian "Kõigi maade proletaarlased, ühinege". It was impossible in 1939, before Mercader's mission to Mexico, as Estonia, along with two other Baltic states, was admitted (annexed rather) to The Soviet Union only in 1940.
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