Retroflex initials in the history of Southern Guanhua phonology

During most of its history the Guānhuà koine is thought to have been rooted in the southern Mandarin dialects of the Yangtze watershed. However, the earliest alphabetic recordings of this language, dating from the mid-fifteenth century, show that it had certain distinctly northern characteristics. The present paper studies one of the features, i.e., retroflexion of certain syllable initials, and concludes that this is attributable to northern migration into the Nanking area from mid-Yuán to early Ming times. Subsequently, the koine came under increasingly heavy southern influence, resulting in competing non-northern forms in the lexicon. These probably became dominant later in the history of the koine.