September 19 or 20, 1486 - April 2, 1502: Age 15
When Arthur, Prince of Wales, was born a month early, he still seemed a healthy child. He was named after the legendary King Arthur of Britain, and he himself was heir to the British throne.
When he was two years old he was contracted to marry the youngest daughter of the same Ferdinand and Isabella who financed Christopher Columbus' voyage to the New World. As he was growing up, he was heaped with honours and tutored by the finest minds in the kingdom. He and his bride-to-be wrote formal letters to one another in Latin. In November 1501, when he had turned 15 years old, the two met at a Palace in Hampshire, and were married ten days later.
Their marriage was very short. Arthur and his new bride, living in Wales, became very ill and, just over four months after the wedding, Arthur died. It is thought that he may have had what they called "sweating sickness", which is now presumed to be a form of hantavirus, or he may have had consumption or diabetes. Suddenly his younger brother Henry, who was just nine years old and destined for a career in the Church, became heir to the throne.
Catherine, who recovered from the fever only to find herself a 16-year-old widow of uncertain status. Because their marriage had been so short and, according to her, unconsommated, the normal procedure would have been for her to return, with her dowry, to her parents, and find someone else to marry. But her father-in-law, a notorious miser, could not bring himself to part with the money. Instead he made vague promises about her marrying the new heir, but since he was only nine years old the whole thing would have to be put off until the young man was old enough to marry. For eight years Catherine was isolated, living on a tiny allowance, unable to pay her staff, and having no official status.
Everything turned up roses when the old king died in 1509. Young King Henry immediately announced his intention to go ahead with the marriage, and for 15 years the two enjoyed a famously loving and happy union. But then, we all know how that ended.
How different the history of England, Europe, and the world would be had Arthur not died so young.