Rainier III, Prince of Monaco Rainier III, Prince of Monaco Rainier III (Rainier Louis Henri Maxence Bertrand Grimaldi; 31 May 1923 – 6 April 2005) ruled the Principality of Monaco for almost 56 years, making him one of the longest ruling monarchs in European history. Though internationally known for his marriage to American actress Grace Kelly, he was also responsible for reforms to Monaco's constitution and for expanding the principality's economy beyond its traditional casino gambling base. Gambling accounts for only approximately three percent of the nation's annual revenue today; when Rainier ascended the throne in 1949, it accounted for more than 95 percent. Rainier
Prince's Palace of Monaco heiress of Cardinal Mazarin. Thus Monaco's ruling family acquired all the estates bequeathed by Cardinal Mazarin, including the Duchy of Rethel, and the Principality of Château-Porcien. Honoré III was a soldier who fought at both Fontenoy and Rocourt. He was happy to leave Monaco to be governed by others, most notably a former tutor. It was on one of Honoré III's rare visits to the palace in 1767 that illness forced Edward, Duke of York, to land at Monaco. The sick duke was allocated the state bedchamber where he promptly died. Since that date the room has been known as