When was Marxism established?
Communism
Marxism, first developed by Karl Marx and Friedrich Engels in the mid-1800s, has been the foremost ideology of the communist movement. Marxism considers itself to be the embodiment of scientific socialism, and rather than model an "ideal society" based on intellectuals' design, it is a non-idealist attempt at the understanding of society and history through an analysis based in real life. Marxism does not see communism as a "state of affairs" to be established, but rather as the expression of a real movement, with parameters which are derived completely from real life and not based on any intelligent design. Therefore, Marxism does no blueprinting of a communist society and it only makes an analysis which concludes what will trigger its implementation and discovers its fundamental characteristics based on the derivation of real life conditions.
Sorelianism
Sorel claimed that although Marx had initially denounced Pierre-Joseph Proudhon while supporting Blanquism, that Marx later synthesized ideas from both Blanquism and Proudhonism together. Sorel claimed that Marxism had undergone a crisis in the 1880s and the 1890s when major socialist parties were being founded in France. Sorel viewed non-Proudhonian socialism as being wrong-headed and corrupt, as being inherently oppressive. Sorel claimed that a "decomposition of Marxism", as referring to the major goals and themes of the ideology, was being caused by Marx's Blanquist elements and Engels' positivist elements.