The person who would have been Louis XVII was born Louis-Charles, the younger son of King Louis XVI of France and Queen Marie Antoinette. He was at birth given the title Duke of Normandy, his older brother, Louis Joseph, died in June 1789, a little over month before the start of the French Revolution. At his brother's death Louis-Charles became the heir-apparent to the throne and the Dauphin of France, a title he would hold until 1791, when the new constitution accorded the heir apparent the style of Prince Royal of France.

When his father was executed on 21 January 1793, he became "King of France" only in the eyes of the royalists. However, since France was by then a republic, and Louis XVII had been imprisoned from August 1792 until his death from illness in 1795 at the age of 10, he was never actually crowned king. His title was bestowed by his royalist supporters and his uncle (Louis Stanislas Xavier, brother of Louis XVI) adopted the regnal name Louis XVIII rather than Louis XVII, upon the Bourbon Restoration in 1814.

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