There are few more storied chapters in Scottish, or indeed British, socialist history than the Red Clydeside era, a period of industrial agitation and political radicalism which spanned the early decades of the twentieth century. Among its leaders was John Maclean, a schoolteacher from the outskirts of Glasgow who would go on to become one of the best-known figures of Scottish politics.

A fiery orator, Maclean rose to prominence as a vocal opponent of the First World War, challenging the British government’s demands for dilution and conscription. In 1915, this saw him charged with sedition under the Defence of the Realm Act, sacked from his teaching job and ultimately imprisoned for a year.

On his release he committed himself full-time to Marxist agitation, continuing to organize industrial militancy across Scotland with the Clyde Workers’ Committee. He also developed links with the revolutionary government in Russia, becoming the Bolshevik consul in Scotland. It was for this combination of activities that he was arrested again, charged with sedition and industrial conspiracy, in April 1918.