Area studies have been facing challenges from many directions in the past few decades, Southeast Asian studies at Berkeley was no exception. Jeffrey Hadler was among the last generation trained in the 20th century area studies traditions; his representative work is firmly grounded in the careful study of the Minangkabau society of Indonesia, which has exerted a significant impact on my research on the leftwing networks of Singapore, Malaya, and Thailand after the Communist Party of Indonesia’s failed revolts in 1926 and 1927. Reflecting on such cross-boundary connections, this paper shows that Hadler‘s scholarship has much broader implications beyond the Minangkabau or Indonesian history. Moreover, as a historian hired in an unconventional area studies department, he actively engaged in intra-region comparisons, cross-region dialogues, and interdisciplinary studies of religions, arts, literature, anthropology, and politics. While fighting for area studies at Berkeley, he was deeply committed to cultivating the field through his innovative research and teaching, as well as academic services, library collections, and other forms of institution building, which created lasting legacies for the Southeast Asian community and beyond.