The group, some of whom had previously been members of the Labour Party, aimed to build a base in industrial southeast Wales by focusing on socialism and republicanism rather than on rural affairs, pacifism and the Welsh language.

It stood Ithel Davies in Ogmore in the 1950 general election, and took 1.3% of the vote.

Some members of the party were arrested for burning the Union Jack, and it faced accusations of initiating violence.

They also conceived a Welsh republican flag, a tricolor with green, red and white bands.

By the mid-1950s, most members of the Movement had either returned to Plaid Cymru or joined the Labour Party, and its newspaper ceased publication in 1957.