How did Karl Marx and Friedrich Engels develop Marxism?

The development of Marxism was the result of a nearly 40-year collaboration between Karl Marx and Friedrich Engels, rooted in their shared conviction that European society required a fundamental transformation to resolve the systemic injustices of capitalism.1

Their partnership began in Paris, where they united to promote the socialist movement. They developed their core ideas through:2

• Theoretical Foundation: Marx established the scientific basis of their theory, focusing on a materialist conception of history, a critique of capitalism, and the necessity of a revolutionary transition to communism.1
• Joint Publications: Their collaboration produced foundational texts such as The German Ideology and the Manifesto of the Communist Party, the latter of which served as the platform for the Communist League.12
• Division of Labor: While Marx was the primary theoretician, Engels provided critical insights into industrial operations, military matters, and science. Engels also supported Marx financially and acted as a key advocate, popularizing their views through works like Anti-Dühring and completing volumes of Das Kapital after Marx's death.23

Together, they argued that the proletariat must overthrow the capitalist system to establish a society where the means of production are publicly owned for the benefit of all.14