A delegate at the 1914 congress of the Social Democratic Youth League, Olsson was thereafter one of the first Swedish communists to undergo political training in Soviet Russia.

In October 1929 the split was final, as Kilbom, Olsson, Flyg and their followers were expelled from the party by the Executive Committee of the Communist International (through its representative Kullervo Manner).

[4] In 1937, Olsson and communist parliamentarian Knut Senander presented a joint motion to repeal the 1899 Åkarp Law, that was perceived as anti-labour.

[2] When Folkets Dagblad Politiken reappeared in 1942, Olsson was again named editor of trade union affairs of the newspaper.

Olsson argued that in circumstances such as the war between Finland and the Soviet Union the party ought to support the right of self-determination of smaller nations.