China has, by one count, 299 mutually unintelligible languages from several different language families, as well as a far greater number of dialects. Linguistic diversity on this scale poses great problems for communication, administration and, in the modern era, national unity and identity. This chapter will explain how the Chinese state has addressed these problems, and it will also explain how the state has regulated language as a strategy of social and ideological control. Its main focus is on the post-totalitarian era that began in 1978, but it will situate that era in the context of Chinese history. It will reveal striking continuities between China’s imperial past and its post-totalitarian present, as well as developments related to the economic, ideological and political changes of the modern era.