When, in 1887, I began the critical study of the History of the United States from 1850 to 1860, I was struck with the paucity of material which would serve the purpose of an animated narrative. The main facts were to be had in the state papers, the Statutes, the _Congressional Globe_ and documents, the records of national conventions and platforms, and the tabulated results of elections. But there was much less private correspondence than is available for the early history of our country; and, compared with the period of the Civil War and later, a scarcity of biographies and reminiscences, containing personal letters of high historical value. Since I wrote my first two volumes, much new matter concerning the decade of 1850 to 1860 has been published. The work of the American Historical Association, and of many historical societies, the monographs of advanced university students, have thrown light upon this, as they have upon other periods, with the result that future delvers in this field can hardly be so much struck with the paucity of material as I was twenty-one years ago. Boy though I was during the decade of 1850 to 1860, I had a vivid remembrance of the part that the newspaper played in politics, and the thought came to me that the best way to arrive at the spirit of the times was to steep my mind in journalistic material; that there was the secret of living over again that decade, as the Abolitionist, the Republican, the Whig, and the Democrat had actually lived in it. In the critical use of such sources, I was helped by the example of von Holst, who employed them freely in his volumes covering the same period, and by the counsel and collaboration of my friend Edward G. Bourne, whose training was in the modern school. For whatever training I had beyond that of self came from the mastery, under the guidance of teachers, of certain general historians belonging to an epoch when power of expression was as much studied as the collecting and sifting of evidence. While considering my materials, I was struck with a statement cited by Herbert Spencer as an illustration in his "Philosophy of Style": "A modern newspaper statement, though probably true, if quoted in a book as testimony, would be laughed at; but the letter of a court gossip, if written some centuries ago, is thought good historical evidence." At about the same time, I noticed that Motley used as one of his main authorities for the battle of St. Quentin the manuscript of an anonymous writer. From these two circumstances, it was a logical reflection that some historians might make an exaggerated estimate of the value of manuscript material because it reposed in dusty archives and could be utilized only by severe labor and long patience; and that, imbued with this idea, other historians for other periods might neglect the newspaper because of its ready accessibility.