My project explores the relationship between science, nation-building, and national identity by examining the development of modem geology in China during the fractured and tumultuous Republican Era (1911-1949). I propose a cultural history centered on the leadership activities of four foundational geologists: Zhang Hongzhao, Ding Wenjiang; Li Siguang, and Weng Wenhao. Based on archival material in China I will address four related questions: How was patriotism used to justify centralized geological activity when China's national identity was divided and contested? Why was geology such a popularly accepted outlet for national feeling? How did the actual practice of geology reshape its own nationalizing objectives? How did the nascent geological community respond to powerful external determinants of national identity (e.g., Japanese invasion)?