The development of my modern history is accompanied by two main lines. The first main line is the deepening of the national crisis. With the Opium War in 1840, China began its modern history, but the defeat made China sign the first unequal treaty "treaty of nanking", and China began to be served by a semi-feudal society. The Second Crushing War, the Sino-French War, the Sino-Japanese War of 1894-1895 and Eight-Nation Alliance's invasion of China started again, which completely reduced China to a semi-colonial and semi-feudal society. During these wars, the Qing government signed many unequal treaties, and China's sovereignty was losing day by day. Therefore, the national crisis has become a deepening trend. Under the background of the deepening national crisis, the movement of saving the nation from extinction is also growing. There is a Westernization Movement initiated by the landlord class Westernization School with the slogan of becoming rich and strong, and there is also a hundred-day reform initiated by the bourgeois reformists, trying to save the country through institutional changes. At the beginning of the 20th century, the Revolution of 1911 led by revolutionaries ended the feudal monarchy that ruled China for more than 2,000 years and established the Republic of China. However, history has proved that the capitalist road is not feasible in China, so after the May 4th Movement, the proletariat, as an independent political force, stepped onto the historical stage and started the new-democratic revolution. Under the scientific leadership of China, the new democratic revolution finally won in 1949! It ended the semi-colonial and semi-feudal social state in China.