Handwritten in the seventeenth century, the Arte de la lengua chio chiu is the oldest extant grammar of the Chinese vernacular known as Southern Min or Hokkien, and a spectacular source text for present-day linguistics. Its author, a Spanish Dominican missionary, worked among the Chinese settlers in Manila or "Sangleys". The first part of The Language of the Sangleys is an in-depth analysis of the Arte in its historical, social and linguistic contexts. The second part offers an annotated transcript and translation of the Arte, including facsimiles of the original manuscript, making this study eminently fit for classroom use. Combining sophisticated theory and method with meticulous philology, The Language of the Sangleys presents a fascinating, new chapter in the history of Chinese and general linguistics.