Louis, author of the *Dictionnaire Historique* which bears his name, was born at Bargemon, in Provence, on the 25th of March 1643. He received the elements of his education at Draguignan and at Aix, and after studying theology at Lyons, where he acquired a knowledge of the Italian and Spanish languages, he took priest's orders. At the age of eighteen he composed the *Pays d'Amour*, a frigid allegory, and, under the title of the *Doux Plaisir de la Poésie*, made a collection of pieces in verse possessing but little merit. But the idea which had long occupied his mind was the composition of his Dictionary, which appeared at Lyons in 1673, in one volume folio, when he was only thirty years of age. The immense erudition displayed in this work excited general admiration; but, as might have been expected, it was found to be very incomplete. The author, however, applied himself with great vigour to enlarge it; but was cut off by death at Paris on the 10th July 1680, at the premature age of thirty-eight. The second edition, in two volumes folio, was printed at Paris in 1681, the year after his death. The third edition, which appeared in 1683, is merely a reprint of the second; but in 1689 a third or supplemental volume was published; and the whole, revised, corrected, and enlarged by Leclerc, was afterwards printed at Amsterdam, 1691, in four volumes folio. To the imperfections of this dictionary we are indebted for that of Bayle, who at first proposed only to correct the errors or supply the omissions of Moreri. The principal defect of Moreri's work consists in the inaccuracy of the geographical portion, in the awkward jumble of mythology and history, in his perplexed nomenclature, and the number and prolixity of his genealogies; but he has nevertheless the merit of being the author of the first work in which are found the names of all those personages who have any title to celebrity. Moreri was also the editor of the *Vies des Saints*, in three volumes, and of De Chignon's *Relation Nouvelle du Levant*, or treatise on the religion, government, and customs of various eastern nations. Besides collecting materials for an historical and bibliographical dictionary of celebrated Provençals, he had commenced a History of the Counsellors; and left in manuscript a treatise on New Year's Gifts.