The Treatise on the Mahāyāna Awakening of Faith, an indigenous Chinese composition written in the guise of an Indian Buddhist treatise, is one of the most influential texts in the history of East Asian Buddhism. Its outline of the doctrines of buddha nature (foxing), buddha bodies (foshen), and one mind (yixin), among others, served from the medieval period onwards as one of the main foundations of East Asian Buddhist thought and practice. The Treatise is putatively attributed to the Indian writer Aśvaghoṣa, and its current Chinese version was traditionally conceived of as a translation from an original Sanskrit text. In the course of the twentieth century, however, many important scholars of Buddhism have called into question the textual history of the Treatise. Even if the specific circumstances of its creation are still largely unknown, the view that the Treatise is an original Chinese composition (not necessarily written by a native Chinese) is now prevalent among scholars. Meanwhile, and for more than one hundred years, the text has also become a source of knowledge of Buddhism in the West thanks to a number of English translations. After examining the early textual history of the two existing versions of the text, this article will offer some examples of its modern appropriation by a novel group of readers and interpreters, an appropriation that took place during the first decades of the twentieth century amidst efforts to re-envision Chinese and East Asian Buddhist history and the place of Buddhism in modern society.