<p>This dissertation examines the modern transformation of orthodoxy within the Otani denomination of Japanese Shin Buddhism. This history was set in motion by scholar-priest Kiyozawa Manshi (1863-1903), whose calls for free inquiry, introspection, and attainment of awakening in the present life represented major challenges to the prevailing orthodoxy. Judging him a principal player in forging a distinctively modern Buddhism, many scholars have examined Kiyozawa's life and writings. However, it is critical to recognize that during his life Kiyozawa remained a marginal figure within his sect, his various reform initiatives ending in failure. It was not until 1956 that Otani leaders officially endorsed and disseminated Kiyozawa's views. Taking my cue from Talal Asad's critique of Clifford Geertz's definition of religion, I move beyond interpretation of the "meaning" of Kiyozawa's life and writings to the historical study of how they came to be invested with authority, impacting the lives of millions of sect members and influencing the perception of him among scholars. </p><p> I approach this history on three levels. On an individual level, I examine the lives and writings of Kiyozawa, his followers, and his critics, as revealed in their books, journal articles, newspaper articles, diaries, and letters. On an institutional level, I examine the transformation of the Otani organization's educational, administrative, and judicial systems, as documented in institutional histories, denominational by-laws, official statements, and administrators' writings. Finally, on a national level, I examine the effect of major political events and social trends on Kiyozawa's followers and the Otani organization. </p><p> This study reveals that one critical factor in the transformation of Otani orthodoxy was the strategic use of a discourse of "empiricism" by Kiyozawa's followers. As the Otani organization's modern university gradually came to supercede its traditional seminary, Kiyozawa's followers positioned themselves as authoritative modern scholars. At the same time, this study shows that the transformation of Otani orthodoxy was contingent upon broader historical developments far outside the control of Kiyozawa's followers or Otani leaders. Specifically, the state's persecution of Communists, war mobilization policies, and the post-war context of democracy building all shaped the views and fortunes of Kiyozawa's followers. I argue that by better acknowledging and examining the contingent nature of religious history, scholars can approach a more realistic view of how religions are formed and reformed. Specifically in regard to modern Buddhist studies, I also argue that more attention should be paid to how sectarian institutions continue to grow and evolve, shaping all aspects of Buddhist thought and practice.</p> / Dissertation