In composing this sketch of Papal history, or, rather, study of its critical phases, I have gratefully used the larger modern histories to which I have referred. Dr. Ludwig Pastor's _History of the Popes from the Close of the Middle Ages_[1] is, for the period it covers (1300-1550), the most valuable of all Papal histories. The Catholic author is not less courageous than scholarly, even if we must recognize some inevitable bias of affection, and he has enriched our knowledge by a most judicious and candid use of unpublished documents in the Secret Archives of the Vatican. Dr. H.K. Mann's _Lives of the Popes in the Middle Ages_,[2] which covers the ground from Gregory I. to Innocent III., is based upon an ample knowledge of the original authorities, but is much less candid and reliable, and seems to be intended only for controversial purposes. Dr. Creighton's learned and judicious _History of the Papacy from the Great Schism to the Sack of Rome_[3] must be corrected at times by the documents in Pastor. Father H. Grisar's incomplete _History of Rome and the Popes in the Middle Ages_[4] is a learned and moderate partisan study of the Papacy in the first four centuries. The older works of Dr. J. Langer,[5] Dean Milman,[6] Gregorovius,[7] and Ranke are by no means superfluous to the student, though more recent research or judgment often corrects them. Less extensive works will be noted in the course of each chapter, and I owe much to industrious older authorities like Baronius, Tillemont, Raynaldus, Mansi, etc. I have, however, had the original authorities before me throughout. The earlier chapters are, indeed, based almost entirely on the Latin or Greek sources, and, in the later chapters, at every point which seemed to inspire differences of judgment I have carefully weighed the original texts. For the later mediæval period, however, Creighton, Pastor, and Gregorovius have so generously strengthened their works with quotations and references that, except at a few points, I may direct the reader to their more comprehensive studies. The narrow limits which are imposed by the particular purpose of this work forbid either the constant quoting of passages or the design of enlarging on some of the remarkable scenes to which it at times refers. The severe condensation, after the first few chapters, has entailed a labour only second to that of research, and I can only trust that the abundance of fact will afford some compensation for the lack of elegance. Happily the earlier controversial method of writing Papal history has so far yielded to candid research that the points in dispute--as far as fact is concerned--are comparatively few. Where they occur--where grave and accepted historians of any school dissent--the evidence is more liberally put before the reader. J.M. Christmas, 1915. FOOTNOTES: [Footnote 1: English trans., 1891, etc.] [Footnote 2: Ten vols., 1902-1914.] [Footnote 3: Six vols., 2d ed., 1897.]