Abstract: Marx and Engels stated that history is people and their activities in the real world, a sequential alternation of ages, and a product of reality rather than a product of pure thought. This argument denies the conclusion that the history is created by people according to the concept in the mind, which establishes the materialism in the field of social history. Marx pointed out that the continuous breakthrough of national and regional restrictions for human production and communication has made human history bound to move towards unity in the end. The meaning of the term "world history" proposed by Marx at different levels are studied, and the course of national history turning into world history is overviewed and summarized based on the text reading of The German Ideology and The Communist Manifesto. Finally, the essence of national history turning into world history is the grasp of real nature of mankind, the union of all people on the basis of the elimination of private ownership and division of labor, and the liberation of people.

Key words: world history, The Communist Manifesto, The German Ideology