Fr. Mariani focuses on Christian resistance in post-1949 China. His most recent work, "Church Militant: Bishop Kung and Catholic Resistance in Communist Shanghai," explores church/state conflict in a time of mounting tension between the newly victorious Chinese Communist Party and Shanghai’s well-organized Catholic community. His book investigates the impact early party campaigns had on one particular social sector, and questions the received wisdom as to whether the 1950s were such a “golden age” for China after all. In addition, Fr. Mariani also teaches survey courses in Premodern China, Modern China, and Modern East Asia. He is also developing a course on the History of Christianity in China.