Caroline, Princess of Hanover Caroline, Princess of Hanover Caroline, Princess of Hanover (Caroline Louise Marguerite Grimaldi; born 23 January 1957), is the eldest child of Rainier III, Prince of Monaco, and the American actress Grace Kelly. She is the elder sister of Prince Albert II and Princess Stéphanie. Until the births of her niece and nephew, Princess Gabriella and Prince Jacques, in December 2014 she had been heir presumptive to the throne of Monaco since 2005, a position which she previously held from 1957 to 1958. Caroline is married to Ernst August, Prince of Hanover (born 1954), the heir to the former throne of
Albert I, Prince of Monaco soon suspended by the Prince when World War I broke out. Also in 1911, Prince Albert created the Monte Carlo Rally, an automobile race designed to draw tourists to Monaco and the Casino. Despite his military service, or perhaps because of it, the Prince became a pacifist, establishing the International Institute of Peace in Monaco as a place to develop a peaceful settlement for conflict through arbitration. In the tension-filled times leading up to World War I, Prince Albert made numerous attempts to dissuade Germany's Kaiser Wilhelm II from war. When war came, Prince Albert could not avoid becoming involved.