Why did the Russian Social Democratic Labour party split in 1903?
The Russian Social Democratic Labour Party sought to unite the different factions of Marxist thought that was present in Russia at the time. Great dissatisfaction with the Czarist regime had facilitated much in way of articulation of Marxist philosophy in Russia. The party felt that the presentation of a unification of the different factions would make Marxist thought in Russian politics more credible.
In 1902, a young Lenin had made his presence known throughout the party. It had become clear that Lenin and a group of his followers advocated a much more radical and strict approach to change in Russia than the rest of the party. Lenin and his group, later to be termed as "Bolsheviks," favored a complete dissolution of the Russian government and replaced with a "vanguard of the proletariat" who would be responsible for leading Russia into a Marxist political and economic vision. In his pamphlet entitled "What is to be Done?" and in his continual efforts to move the party more to his point of view, a split was inevitable. Lenin's Bolsheviks were diametrically opposed to the Mensheviks, led by Martov, who favored strengthening the legislative branch of Russian government, the Duma, as a means to achieving change in Russia. The party's competing philosophies of Bolshevism and Menshevism led to the split in 1903.