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 the 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.