This article explores the history of four Chinese vernaculars which have elaborated written forms, and asserts that five of the patterns Hanan distinguishes in the early development of Bai Hua, can also be perceived in the early development of written Minnan, Cantonese, and Wu. The vigor of the recurring patterns, detected in cases that diverge in both social and historical contexts, indicates that they are anchored in inherent qualities of L varieties in diglossic situations.