Partido Obero de Unificacion Marxista
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The Partido Obero de Unificacion Marxista (or POUM) was a Spanish communist political party. They fought for the Republicans during the Spanish Civil War. The POUM differed from the Russian communists and opposed Stalin.
In Barcelona, the POUM were involved in street fighting against the regular communists. Fitz Kreiner fought alongside Joaquín - a POUM member - in the fighting. After the fighting subsided, the POUM were accused of inciting violence among the Republican forces in an attempt to aid Nationalist forces. (EDA: History 101)