This essay reviews Alan Richard Sweeten’s latest book, entitled China's Old Churches: The History, Architecture, and Legacy of Catholic Sacred Structures in Beijing, Tianjin, and Hebei Province, which explains in colourful detail how urban and rural Catholics across northern China manifested their ecclesial identity through architecture and iconography. This timely and comprehensive account historicizes the images and designs of prominent Catholic churches, creating a visual overview of an immensely agitated period and region, revealing unprecedented dangers and challenges for evangelization, as well as freedom and opportunity for cross-cultural collaboration. Sweeten contextualizes the enduring process of Christianization within the actions of religious adaptation and adjustment, empire transition, and cross-cultural engagement between Western missionaries and indigenous actors.