How long did the reign of the French King Louis XIX last?

Louis Antoine of France, Duke of Angoulême (6 August 1775 – 3 June 1844) was the elder son of Charles X of France and the last Dauphin of France (the heir apparent) from 1824 to 1830. He was technically King of France and Navarre for less than 20 minutes before he himself abdicated, due to his father's abdication during the July Revolution in 1830. He never reigned over the country, but after his father's death in 1836, he was the legitimist pretender as Louis XIX.

Masses of angry demonstrators demanded the abdication of Charles and of his descendants in July 1830, in what became known as the July Revolution, in favour of his cousin Louis Philippe, Duke of Orléans. They sent a delegation to the Tuileries Palace to force his compliance.

Charles reluctantly signed the document of abdication on 2 August 1830. It is said that Louis Antoine spent the next 20 minutes listening to the entreaties of his wife not to sign a similar document, while the former Charles X sat weeping. However, he also abdicated, in favour of his nephew, the Duke of Bordeaux. For the final time he left for exile, where he was known as the "Count of Marnes". He never returned to France.

Louis Antoine and his wife travelled to Edinburgh, Scotland, in November 1830 and took up residence in a house at 21 (now 22) Regent Terrace near Holyrood Palace where Charles X was staying.