of the Menshevik Party in opposition to Lenin’s Bolsheviks. He had at first cooperated with Lenin as joint editor of Iskra (‘The Spark’), but, at the meeting of the second Russian Social Democratic Party in London (1903), they disagreed over the degree of revolutionary class-consciousness in the labour movement and the extent to which it had to be controlled by a small party. Mensheviks favoured a mass labour party. After 1917 he supported Lenin against the “White” armies but continued to oppose his more dictatorial policies. He left the Soviet Union in 1920.