There has hitherto been no satisfactory text of this treatise. The first printed edition, that of Ulrich von Hutten, in 1517, is excessively rare, and it, as well as its numerous reprints, is defective in places. The same is true of the text in the collected works of Valla, the Opera, printed at Basle, 1540, 1543 (?). The only English edition, by Thomas Godfray (London, 1525?), is rare and of no great merit. A modern French edition by Alcide Bonneau (La Donation de Constantin, Paris, 1879) gives the text with a French translation and a long introduction. It is based on the 1520 reprint of Hutten’s edition, is polemical, uncritical, and admittedly imperfect. A modern edition with translation into Italian (La dissertazione di Lorenzo Valla su la falsa e manzognera donazione di Costantino tradotta in Italiano da G. Vincenti, Naples, 1895) is out of print. My text is based on the manuscript Codex Vaticanus 5314, dated December 7, 1451, the only complete manuscript of the treatise I have been able to find. I have collated this with Hutten’s text as found in one of the earliest, if not the earliest, reprint (contained in the little volume De Donatione Constantini quid veri habeat, etc., dated 1520 in the Union Theological Seminary library copy, but corresponding closely to the one dated 1518 in E. Böcking’s edition of the works of Ulrich von Hutten, vol. I, p. 18), and have occasionally used readings from Hutten’s text or later ones, such as that of Simon Schard,[4] but in every instance I have indicated the MS. reading. I have used uniform, current spelling and punctuation, and have used my own judgment in paragraphing. Preceding Valla’s treatise I reprint, with a translation, the text of the Donation as given, with the omission of long sections, in Gratian’s Decretum, or Concordia discordantium canonum, which was the form Valla used and on which he based his criticism. I take it from A. Friedberg’s edition of the Corpus Iuris Canonici, vol. I, columns 342-345. The full text of the Donation is best given by Karl Zeumer, in the Festgabe für Rudolf von Gneist (Julius Springer, Berlin, 1888), pp. 47-59, reprinted among other places in my Constantine the Great and Christianity, pp. 228-237. The document may be studied to advantage also in the Decretales Pseudo-Isidorianae et Capitula Angilramni, ed. Hinschius (Leipsic, 1863). An English translation, from Zeumer’s text, is in E. F. Henderson’s Select Historical Documents of the Middle Ages, pp. 319-329. In the translation of passages of the Donation I have, so far as possible, used the words of Henderson’s translation. In quotations from the Bible I have used the King James version. In translating Valla’s quotations from the Donation I have usually, though not always, followed him in giving words their classical and not their medieval meaning.