The obligations incurred in the preparation of the following study are much too numerous and varied to admit of adequate notice. Special mention must, however, be made of my indebtedness to the staffs of the following libraries: The Boston Athenaeum, Congregational, Masonic (Boston), American Antiquarian Society, Connecticut Historical Society, New York Historical Society, Library of Congress, the public libraries of the cities of Boston and New York, the library of Hiram College, and the university libraries of Harvard, Yale, and Columbia. In addition to the many courtesies received from these sources, I have had valuable assistance from the following persons: Mr. Newton R. Parvin, grand secretary of the Grand Lodge of Iowa, A. F. & A. M., Cedar Rapids, Iowa, whose warm personal interest in my investigation has found expression in the loan of many valuable volumes; Mr. Worthington C. Ford, of the Massachusetts Historical Society, who besides opening freely to me the unpublished treasures of the Society, has given me the benefit of peculiarly stimulating suggestions; Mr. Walter C. Green, librarian of Meadville Theological School, who has most generously met all my drafts upon his patience and time; and Professor Guy Stanton Ford, of the University of Minnesota, who has made it possible for me to use his copy of Forestier’s _Les Illuminés de Bavière et la Franc-Maçonnerie allemande_, without which in this war period, with its partial stoppage of the inflow of European literature, my chapter on “The European Order of the Illuminati” could scarcely have been written. My greatest debt is to Professor William Walker Rockwell, of Union Theological Seminary, who from the day that he suggested the theme not only has followed the progress of the work with unwearied interest, but at many points has guided my efforts and helped me to avoid numerous pitfalls. Whatever excellencies the study contains are due to Professor Rockwell’s stimulating criticism; the faults are altogether chargeable to me. There remains to acknowledge my obligation and express my best thanks to my colleagues, Professors Ralph Hinsdale Goodale, Lee Edwin Cannon, and John Samuel Kenyon, and to Miss Bertha Peckham, Registrar of Hiram College, who have greatly assisted me by correcting copy, reading proof, and otherwise helping to see the work through the press. To my wife a special obligation is due because of the benefits derived from her critical insight and heartening sympathy throughout the performance of the task. V. S. HIRAM, OHIO. INTRODUCTION