Guo Zhengyi, official of the Chinese Tang dynasty

Guo Zhengyi was a Chinese politician of the Chinese Tang dynasty, serving as a chancellor during the reign of Emperor Gaozong and the regency of Emperor Gaozong's powerful wife Empress Wu over their son Emperor Zhongzong.

The history of China spans several millennia across a wide geographical area. Each region now considered part of the Chinese world has experienced periods of unity, fracture, prosperity, and strife. Chinese civilization first emerged in the Yellow River valley, which along with the Yangtze basin constitutes the geographic core of the Chinese cultural sphere. China maintains a rich diversity of ethnic and linguistic people groups. The traditional lens for viewing Chinese history is the dynastic cycle: imperial dynasties rise and fall, and are ascribed certain achievements. This lens also tends to assume Chinese civilization can be traced as an unbroken thread many thousands of years into the past, making it one of the cradles of civilization. At various times, states representative of a dominant Chinese culture have directly controlled areas stretching as far west as the Tian Shan, the Tarim Basin, and the Himalayas, as far north as the Sayan Mountains, and as far south as the delta of the Red River.

The Tang dynasty, or the Tang Empire, was an imperial dynasty of China that ruled from 618 to 907, with an interregnum between 690 and 705. It was preceded by the Sui dynasty and followed by the Five Dynasties and Ten Kingdoms period. Historians generally regard the Tang as a high point in Chinese civilisation, and a golden age of cosmopolitan culture. Tang territory, acquired through the military campaigns of its early rulers, rivalled that of the Han dynasty.