Born as the sole heir to the throne of the nation of Monaco, Prince Rainier III lived his life by duty, driven by a sense of responsibility that was instilled in him from a young age. As the son of Charlotte Grimaldi, the illegitimate daughter of Monaco's Prince Louis, Rainier was the aging monarch's only grandson and was therefore invested as his heir.
The constraints of duty were evident from the start, as Rainier knew that he could not abdicate his throne for any reason, as there was no one else to take it over. By law, Monaco must have a male Grimaldi as ruler, or the principality reverts to the ownership of France. This reality weighed heavily on Rainier, who was forced to make difficult decisions early on in his life.
As a young man, Rainier was forced to break off plans to marry his girlfriend after tests showed she was infertile. While he cared for her deeply, Monaco had to have an heir, and Rainier knew that he had a duty to fulfill this requirement. He soon became known as the wealthiest bachelor in the world, and for a short time, even Marilyn Monroe was considered as a potential bride.
However, Rainier ultimately wed famous film star Grace Kelly in what was termed "the Wedding of the Century". A year later, the new Princess Grace gave birth to their first child, daughter Princess Caroline of Monaco. A year after this event came the birth of their son and heir, Prince Albert of Monaco, Marquis of Baux. A few years later, Princess Stéphanie of Monaco arrived to round out the family.
After the tragic death of Princess Grace in a car accident, Princess Caroline took on her mother's role as Monaco's unofficial First Lady. Caroline has three children by her second husband, Stefano Casiraghi (who died in a speed-boat accident),and a daughter by her third husband, Prince Ernst August of Hanover. Princess Stephanie has two children by her short-lived marriage to bodyguard Daniel Ducruet and an illegitimate daughter, Camille.
Prince Albert remained unmarried, and seemingly inherited his father's former title as the most eligible Prince in the world. Rainier had many health problems in later life, and died in hospital on April 5th 2005, following a long illness, at the age of 81. Following his state funeral, attended by many world dignitaries and royalty, his son formally succeeded him as Prince Albert II of Monaco.