The phonological history of Chinese can be traced back to two main traditions: one starting with the Qieyun of 601, and the other starting with the Zhongyuan Yinyun of 1324. The former marks the beginning of Middle Chinese, and the latter marks the beginning of Old Mandarin. Both of these systems, as well as reconstructed Old Chinese, should be understood as ideal phonological standards and composite in nature. Until modern times, phonological standards were never based strictly on the phonology of a single dialect. This book provides the first study written in English, of the phonological history of Chinese. It provides information about the standard phonological systems for each of the language's major historical periods, drawing on a range of historical materials such as dictionaries, rhyming tables and poetry, and is the reference book for understanding the key developments in the Chinese sound system.