''It incarnates every unclean beast of lust, guile, falsehood, murder, despotism and spiritual wickedness.'' So wrote a prominent Southern Baptist official in 1899, as he viewed with disgust what contemporary scholars have called the "quintessential American religion. " In the late nineteenth century, Mormonism was the most vilified homegrown American religion. A national campaign featuring politicians, church leaders, social reformers, the press, women's organizations, businessmen, and ordinary citizens sought to end the distinctive Latter-day Saint practice of polygamy, and, if necessary, to extinguish the entire religion. Considering the movement against polygamy within American and southern history, Mason demonstrates how anti-Mormonism was one of the earliest grounds for reconciliation between North and South after the Civil War and Reconstruction. Southerners joined with northern reformers and Republicans to endorse the use of newly expanded federal power to vanquish the perceived threat to Christian marriage and the American republic. Anti-Mormonism was a significant intellectual, legal, religious, and cultural phenomenon, but in the South it was also violent. While southerners were concerned about distinctive Mormon beliefs and political practices, they were most alarmed at the "invasion " of Mormon missionaries in their communities, and the prospect of their wives and daughters falling prey to polygamy. In order to defend their homes and their honor against this threat, southerners turned to legislation, religion, and, most dramatically, vigilante violence. The Mormon Menace provides new insights onto some of the most important discussions of not only the late nineteenth century but also our own age, including debates over the nature and limits of religious freedom, the contest between the will of the people and the rule of law, and the role of citizens, churches, and the state in regulating and defining marriage.