Mormonism’s founding decades have received the vast amount of historians’ attention. By contrast, comparatively few historians and sociologists have studied twentieth-century Mormonism. The future of Mormon Studies must involve a fundamental change in that dynamic, particularly in historians’ understanding of the rise of global Mormonism. This chapter traces the developments within Mormonism over the past century, situates the existing historiography, and suggests avenues for future scholarship. In particular, the chapter discusses Mormonism’s “era of transition” in the late 1800s and early 1900s; the relationship between Latter-day Saints and American culture and government throughout the 1900s; and the rise of Mormon congregations throughout the globe in the second half of the twentieth century.