In conventional histories, Lord Lao (Laozi) was a sixth-century BCE official of the Zhou dynasty and the author of the Daode jing (The Book of the Dao and Its Virtue). Thereafter, he gained mythic status as an immortal, a messiah, and a high god of Daoism. After being divinized during the Han dynasty and in early Daoist movements, Laozi reached his highest level of veneration under the Tang when the rulers honored him as a royal ancestor. In...