Overview
Dauphin of France (, also ; ), originally Dauphin of Viennois (Dauphin de Viennois), was the title given to the heir apparent to the throne of France from 1350 to 1791, and from 1824 to 1830. The word dauphin is French for dolphin and was the hereditary title of the ruler of the Dauphiné of Viennois. While early heirs were granted these lands to rule, eventually only the title was granted.
History
Guigues IV, Count of Vienne, had a dolphin on his coat of arms and was nicknamed le Dauphin. The title of Dauphin de Viennois descended in his family until 1349, when Humbert II sold his seigneury, called the Dauphiné, to King Philippe VI on condition that the heir of France assume the title of le Dauphin. The wife of the Dauphin was known as la Dauphine.
The first French prince called le Dauphin was Charles the Wise, later ascending to the throne as Charles V of France. The title was roughly equivalent to the Spanish Prince of Asturias, the Portuguese Prince of Brazil, the English (thence British) Prince of Wales, and the Scottish Duke of Rothesay. The official style of a Dauphin of France, prior to 1461, was par la grâce de Dieu, dauphin de Viennois, comte de Valentinois et de Diois ("By the Grace of God, Dauphin of Viennois, Count of Valentinois and of Diois"). A Dauphin of France united the coat of arms of the Dauphiné, which featured dolphins, with the French fleurs-de-lis, and might, where appropriate, further unite that with other arms (e.g. Francis, son of Francis I, was ruling Duke of Brittany, so united the arms of that province with the typical arms of a Dauphin; Francis II, while Dauphin, was also King of Scots by marriage to Mary I, and added the arms of the Kingdom of Scotland to those of the Dauphin).
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