DAUPHIN, an ancient feudal title in France, borne only by the counts and dauphins of Vienne, the dauphins of Auvergne. and from 1364 by the eldest son of the king of France. The origin of this curious title is obscure; but it now seems clear that it was in the first instance a proper name. It was borne by Guigo, or Guigue IV. (d. 1142), count of Albon and Grenoble, as an addi tional name, during the lifetime of his father, and was also adopted by his son Guigue V. Beatrice, daughter and heiress of Guigue V., whose second husband was Hugh III., duke of Bur gundy, bestowed the name on their son Andre, to recall his de scent from the ancient counts of Albon. His successors Guigue VI. (d. 127o) and John I. (d. 1282) call themselves sometimes Delphinus, sometimes Delphini, the name being obviously treated as a patronymic, and in the latter form it was borne by the sons of the reigning "dauphin." But even under Guigue VI. foreigners had begun to confuse the name with a title of dignity, an imperial diploma of 1248 describing Guigue as "Guigo Dalphinus Vien nensis." It was not until the marriage of Anne, heiress of John I., with Humbert, Lord of La Tour du Pin, that "dauphin" became defi nitely established as a title. Humbert not only assumed the name of Delphinus, but styled himself regularly Dauphin of the Vien nois (Dalphinus Viennensis), and in a treaty concluded in 1285 between Humbert and Robert, duke of Burgundy, the word del phinatus (Dauphine) appears for the first time as a synonym for comitatus (county). In 1349 Humbert II., the last of his race, sold Dauphine to Charles of Valois, who, when he became king of France in 1364, transferred it to his eldest son. From that time the eldest sons of the kings of France were always either actual or titular dauphins of the Viennois.
The eldest son of the French king was sometimes called "the king dauphin" (le roy daulphin), to distinguish him from the dauphin of Auvergne, who was known, since Auvergne became an appanage of the royal house, as "the prince dauphin." The dauphi nate of Auvergne, which is to be distinguished from the county, dates from 1155, when William VII., count of Auvergne, was deposed by his uncle William VIII. William VII. had married a daughter of Guigue IV. Dauphin, after whom their son was named Dauphin (Delphinus). The name continued, as in Viennois, as a patronymic, and was not used as a title until 1281, when Robert II., count of Clermont, in his will, styles himself for the first time Dauphin of Auvergne for the portion of the county of Auvergne left to his house. In 1428 Jeanne, heiress of the dauphin Beraud married Louis de Bourbon, count of Montpensier (d. 1486), thus bringing the dauphinate into the royal house of France. It was annexed to the Crown in 1693.