Tonghak, or Eastern Learning, was the first major new religion in modern Korean history. Founded in 1860, it combined aspects of a variety of Korean religious traditions. Because of its appeal to the poor and marginalized, it became best known for its prominent role in the largest peasant rebellion in Korean history in 1894, which set the stage for a wider regional conflict, the Sino-Japanese War of 1894-1895. Although the rebellion failed, it caused immense changes in Korean society and played a part in the war that ended in Japan's victory and its eventual rise as an imperial...