Charles II of Spain
The Egyptian family was not the only one to inbreed. Throughout the ages, incest was common in the royal family to maintain purity in the bloodline. Similarly, for about two centuries, the Spanish Habsburg dynasty inbreed in order not to share power with outsiders. Hence, as a result in 1700, the last of the family, King Charles II died without an heir that ended the family line.
The Habsburg family was really into maintaining power into the family because before Charles death, 9 of the 11 marriages that took place in the family was between biological relatives. Starting in 1550, nobody within the dynasty married outside of their family. Charles himself was the child of an uncle-niece marriage. By some evaluation, he was one of the most inbred people in history, with 95.3 percent of his genes traceable to just five ancestors. He has many descriptions that were result of the inbreed. One biography described poor Charles as having an “an enormous misshapen head” and a huge tongue. He also had a jaw that “stood so much out that his two rows of teeth could not meet,” which caused frequent drooling, an inability to chew, and extreme difficulty speaking. Others said the king suffered from intestinal upsets, convulsions, premature ejaculation, and impotence.
The dynasty sure was gone but its name still lives among dental professionals who called the prognathism condition of Charles “Habsburg jaw” in respect to the weak, drooling, big-headed king.