Gomułka was an activist in the leftist labor unions from 1926 and in the Central Trade Department of the KPP Central Committee from 1931. In the summer of 1930, Gomułka illegally embarked on his first foreign trip with the intention of participating in the Red International of Labor Unions Fifth Congress held in Moscow from 15 to 30 July. Traveling from Upper Silesia to Berlin, he had to wait there for the issuance of Soviet documents and arrived in Moscow too late participate in the deliberations of the Congress. He stayed in Moscow for a couple of weeks and then went to Leningrad, from where he took a ship to Hamburg, stayed in Berlin again and through Silesia returned to Poland.