PKM was founded in 1969 at a secret congress in the town of Gwardamangia, following the departure from the Malta Labour Party of a group of left-wing militants that had been active in the struggle for national independence.

[1] The party first contested the national general elections of 1987 when it obtained 0.1% of first preference votes and no parliamentary seats.

After the 1933 sedition trials[5] dockyard workers and intellectuals were imprisoned for the "crime" of possessing socialist literature.

The PKM organised protests and meetings as well as commemorations to Maltese working class figures in support of emancipation such as Manwel Dimech.

In 2016, the two groups published a joint statement appealing for a reformation of the neutrality clause in the Constitution of Malta to ban warships from all countries from docking in Maltese ports.