The book is concerned with the Ethnic issues of China in the 20th century in general. It includes the conflicts between the foreign aggression and Democratic Revolution, the ethnic issues, the ethnic policies, the development in Xinjiang, Mongols, Tibet and other regions in China during the 20th century. Since China is a country with 56 nationalities, it adopts its own ethnic policy with Chinese character. What are the historical causes led to such a multiple-nationality Country? Unique aspects to this book include: the detailed analysis on the historical background and reasons for such a multiple-nationality Country, and the vivid description of the ethnic policy in China in different minority nations. This book is a comprehensive study on the ethnic issues in China in three dimensions, from the chronological aspect, the policy making aspect, and the inner and international impact on Chinese ethnic issues.