During the French Revolution, Louis Joseph was a dedicated supporter of the monarchy and one of the principal leaders of the counter-revolutionary movement. After the storming of the Bastille in 1789, he fled France with his son and grandson, before the "Reign of Terror" which arrested, tried and guillotined most of the Bourbons still living in France: Louis XVI, Marie Antoinette and the Duke of Orleans ("Philippe Égalité") were executed in 1793, and the king's sister, Madame Élisabeth, was beheaded in 1794.