– a set of political positions and movements based on the work of Karl Marx and Friedrich Engels. Marx's philosophy of history included the notion of class struggle within dialectical materialism. Marxism was the intellectual foundation for the 20th-century political movement known as Communism, and was developed into various factions such as Leninism, Stalinism, Maoism, and Trotskyism, each hewing to the ideas of a particular political leader.