When the men of long or of transient connection with M. I. D. had shaken hands and said good-bye, the National Directors of the American Protective League asked me to stop on and write the history of the American Protective League. And so, in large part, as a matter of loyalty and duty, with millions of pages of records at hand, with a quarter of a million friends I have never seen, who never have seen one another, who never otherwise would know the identity of one another, I began to do something which most obviously and certainly ought to be done. This book is written alike that these quarter million unpaid soldiers may know of one another, and that a hundred million Americans may also know of them accurately, and thank them for what they did. Before I had done the last page of the strange history, I knew that I had felt an actual reflex of the actual America. I knew that I had been in touch with one of the most astonishing phenomena of modern days, in touch also with the most tremendous, the most thrilling and the most absorbing story of which I ever knew. EMERSON HOUGH _Washington_ _District of Columbia_ _United States of America_ _February 14, 1919._ CONTENTS BOOK I: THE LEAGUE AND ITS WORK CHAPTER PAGE I THE AWAKENING 19 II THE WEB 29 III EARLY DAYS OF THE LEAGUE 38 IV THE LEAGUE IN WASHINGTON 44 V THE LAW AND ITS NEW TEETH 55 VI GERMAN PROPAGANDA 62 VII THE GERMAN SPY CASES 82 VIII THE SPY HIMSELF 107 IX HANDLING BAD ALIENS 120 X THE GREAT I. W. W. TRIAL 133 XI THE SLACKER RAIDS 141 XII SKULKER CHASING 148 XIII ARTS OF THE OPERATIVES 163 BOOK II: THE TALES OF THE CITIES I THE STORY OF CHICAGO 179 II THE STORY OF NEW YORK 199 III THE STORY OF PHILADELPHIA 210 IV THE STORY OF NEWARK 226 V THE STORY OF PITTSBURGH 239 VI THE STORY OF BOSTON 246 VII THE STORY OF CLEVELAND 256 VIII THE STORY OF CINCINNATI 267 IX THE STORY OF DAYTON 276 X THE STORY OF DETROIT 285 XI THE STORY OF ST. LOUIS 293 XII THE STORY OF KANSAS CITY 303 XIII THE STORY OF MINNEAPOLIS 310 XIV THE STORY OF NEW ORLEANS 324 XV THE STORY OF CALIFORNIA 332 BOOK III: THE FOUR WINDS I THE STORY OF THE EAST 363