Charles du Fresne, Sieur du, one of the most learned writers of his time, was born at Amiens, December 18, 1610. His father, who was royal provost of Beaquesne, sent him at an early age to the Jesuits' College in Amiens, where he soon distinguished himself. Having completed the usual course at this seminary, he applied himself to the study of law at Orleans, and afterwards went to Paris, where he was received as advocate before the parliament in August 1631. Meeting with little success as a barrister, he returned to his native country, where he applied himself to the study of history. After the death of his father, Du Cange married at Amiens, on 19th July 1638, Catherine Du Bois, daughter of a treasurer of France; and, in 1647, he purchased the same office, the duties of which in no degree interfered with the great literary works in which he had engaged. The plague, which in 1668 desolated Amiens, forced him to leave that city. He established himself at Paris, where he was enabled to consult charters, diplomas, titles, manuscripts, and a multitude of printed documents, which were not to be met with elsewhere. He was often aided in his researches by his friend M. d'Héronval. Having in 1688 been seized with strangury, he died of its effects on the 23rd October. To the attributes of a good son, a good husband, and a good father, Du Cange united those of extreme gentleness, affability, and modesty. His industry was exemplary and unremitting; and the number of his literary works would be incredible, if the originals, all written in his own hand, were not still extant. In his productions are united the characters of a consummate historian, an exact geographer, a profound jurist, an enlightened genealogist, a learned antiquary, and one deeply versed in the science of medals and inscriptions. He knew most languages, possessed a thorough acquaintance with literature, and from a vast number of manuscripts and original documents drew much curious information respecting the manners and customs of the darkest ages. The learned prefaces of his glossaries afford ample proofs of his philosophical genius, and are, of their kind, models in point both of matter and of style.

Du Cange published the following works:—1. Histoire de l'Empire de Constantinople sous les Empereurs François. Paris, 1657, folio. 2. Traité Historique du Chef de S. Jean-Baptiste. Paris, 1665, 4to. 3. Histoire de S. Louis, Roi de France, écrite par Jean, sire de Joinville. Paris, 1668, folio. 4. Joannis Cinnami Historiarum de rebus gestis a Joanne et Manuele Commentis, libri vii. Graece et Latine, cum Notis historiciis et philologiciis. Paris, 1670, folio. 5. Mémoire sur le projet d'un nouveau Recueil des Histories de France, avec le projet de faire de même Recueil, inséré dans la Bibliothèque Historique de la France, par Père Lelong. 6. Glossarium ad Scriptores medii et infimae Latinitatis. Paris, 1678, 3 vols. fol. 7. Lettre du Sieur N. Conseiller du Roi, à son ami M. Ant. Wion d'Héronval, au sujet des Libelles qui de temps en temps se publient en Flandres contre les RR. PP. Henschenius et Papebruch, Jésuites. Paris, 1682, 4to. 8. Historia Byzantina duplici Commentario Illustrata. Paris, 1680, fol. 9. Joannis Zonarii Annales ab exercicio Mundi ad mortem Alexii Comneni, Graece et Latine, cum Notis. Paris, 1686, 2 vols. fol. 10. Glossarium ad Scriptores medii et infimae Graecitatis. Paris, 2 vols. fol. 11. Chronicon Paschale à Mundo condito ad Heraclii Imperatoris annum vigesimum. Paris, 1689, fol. This last work was being passing through the press when Du Cange died, and before its delivery, it was edited by Baluze, and published with an éloge of the author prefixed. His manuscript autographs, and his extensive and valuable library, passed to his eldest son, Philippe du Fresne, who died unmarried, four years after. François du Fresne, the second son, and two sisters, then received the succession and sold the library, when the greater part of the manuscripts was purchased by the Abbé du Champ, who handed them over to a bookseller called Mariette, who re-sold part of them to Baron Hohendorf. The remaining part was acquired by D'Izquier, the genealogist. But the French government, sensible of the importance of all the writings of Du Cange, succeeded, after much trouble, in collecting the greater portion of the manuscript autographs of this eminent scholar. Among these manuscripts was one entitled Gallica, a work of incredible erudition, being a history of France, divided into seven epochs, with a number of dissertations, the greater part of which are ready for the press, whilst, in regard to those which are not so, abundant materials have been provided for its completion.