6. King Philip IV Married His Niece — She Gave Him Children Who Could Hardly Function
While today we often become disgusted by the idea of close family members marrying each other, it was often common during the 1600s. However, if they did marry into their own family, they often married cousins, usually distant cousins. But this was not the case for King Philip IV of Spain. Instead of marrying a distant cousin, he chose to marry his niece. On top of this, King Philip should have especially known this would turn out to be a bad idea because so many other relatives of his had already married family members.
Because of this, many people of this line were born with deformities and others had died due to their condition. King Philip and his niece married in 1644 and had King Charles II. While childhood paintings would show Charles II as looking like an average kid, he reportedly had the “Hapsburg jaw,” which created difficulties in chewing. King Charles II also regularly dealt with illnesses throughout his life, including excessive vomiting. Genetic tests show that there was so much inbreeding by the time Charles II was born that he was comparable to if a brother would have impregnated a sister.