Active in opposition to the First World War, he joined the Anti-Parliamentary Communist Federation and became its treasurer, but soon left after disagreements with Guy Aldred.
[7] In 1937, McGovern led an ILP commission of enquiry into the affairs of the Republicans in the Spanish Civil War.
This was ostensibly to counter allegations made by prominent Catholics concerning Republican treatment of prisoners; however, he also aimed to support the Workers' Party of Marxist Unification (POUM), which was increasingly threatened by the communists, and to find information as to the disappearance of Andrés Nin.
When the ILP Chairman C. A. Smith unexpectedly quit the party in 1941 in disagreement with this policy, McGovern was elected in his place, although he held the post for only two years.
[9] He was re-elected for Labour in 1950 and 51, and in 1952 led the campaign to permit Trotskyist Tony Cliff to remain in Britain.