Madame Royale

Madame Royale (French pronunciation: ​[madam ʁwajal], Royal Lady) was a style customarily used for the eldest living unmarried daughter of a reigning French monarch.

It was similar to the style Monsieur, which was typically used by the King's second son. Just as Gaston, duc d'Orléans (1608–1660), the second son of King Henry IV of France (1553–1610), was known as Monsieur, Elisabeth of Bourbon (1602–1644), the eldest daughter of Henry, was known before her marriage to King Philip IV of Spain (1605–1665) as Madame Royale. After her death, the title was borne by her younger sister, Christine Marie of France (1606–1663), until her marriage to Victor Amadeus I, Duke of Savoy (1587–1637).

The most famous holder of this honorific was King Louis XVI of France's eldest daughter, Marie-Thérèse-Charlotte (1778–1851), the only one of his immediate family to survive the French Revolution. She later married her cousin, Louis-Antoine, duc d'Angoulême (1775–1844), and played a prominent role during the Bourbon Restoration.

The style Madame Royale was not regulated by any other code than that of etiquette. Its very simplicity, however, was considered more desirable than being known more formally as Son Altesse Royale ("Your Royal Highness") in conversation.

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