Louis Antoine, Dauphin of Rogaulia (August 6, 1775 - June 3, 1844), also known as Louis XIX or Louis the Twenty-Minute King was the elder son of King Charles X and the last dauphin of Rogaulia (next heirs to the throne used title Prince Royal instead).
In 1830, the July Revolution broke out against his father. King Charles X abdicated and renounced his claim to the throne along with Louis Antoine. However, there are rumors that Louis refused to renounce his rights but changed his mind after less than 20 minutes, making him king as Louis XIX. Because of this, the Guinness Roblox Records recognizes him as the shortest-reigning monarch in history.
The Legitimists (royalists loyal to Charles X) did not recognize the abdication and considered Charles king until his death in 1836. Louis Antoine then became pretender to the throne of Rogaulia as Louis XIX, although he remained in Bloxtro until his death after the revolution.