张道陵
The term "Zhengyi" (Orthodox Unity) has been used since Daoism became an organized religion in 142 AD when Laozi bestowed the Covenant with the Powers of Orthodox Unity ("zhengyi mengwei") on Zhang Daoling. Zhang's followers called his teachings the Way of the Five Pecks of Rice while during the Six Dynasties period, the southern Daoists called it the Way of the Celestial Masters. The Covenant, Five Pecks of Rice, and Celestial Masters all refer to the "Zhengyi" branch of Daoism but in different periods.