China Historical Christian Database: Mapping China’s Christian Past quantifies and visualizes the place of Christianity in modern China (1550-1950). It provides users the tools to discover where every Christian church, school, hospital, orphanage, publishing house, and the like were located in China, and it documents who worked inside those buildings, both foreign and Chinese. Collectively, this information creates spatial maps and generates relational networks that reveal where, when, and how Western ideas, technologies, and practices entered China. Simultaneously, it uncovers how and through whom Chinese ideas, technologies, and practices were conveyed to the West.