Some thought them dangerous, others credited them with recovering original Christianity. The Sandemanians, a sect with roots in the turmoil of eighteenth-century Scottish Presbyterianism, espoused a radical theology that influenced the development of American Christianity. Founder John Glas blended elements of fundamentalist New Testament Christianity with Enlightenment philosophy to create what he believed to be "the perfect rule of the Christian religion." The history and legacy of the Sandemanians are given full attention in these pages, which reveal the origins of the sect in Scotland and follow its greatest proselyte, Robert Sandeman, across the Atlantic to New England. Author John Howard Smith shows how such a minor sectarian movement could create so much controversy at the time of the First Great Awakening and the American Revolution. The churches Sandeman established were eventually crushed by the Revolution, their adherents scattered, never to grow into a denomination. The Sandemanians are little known today, yet elements of their theology played a key role in the future of American Christianity.