The Thickness of the Upper Crust

An afternoon refresher of European history is enough to give an idea of how common inbreeding was among the world’s most prestigious families. Aristocratic bloodlines have the highest rates of traceable inbreeding, and the tradition can be found as early as the Medieval years when marriages between close relatives were common among the ruling elite. 

6 minutes

Politics and power were what it always came down to, old world or new. The negative consequences of inbreeding were not well understood or accepted for most of history. There’s also been a lot of funny theories about blood and genes over time. In nearly all cases, marriages between close relatives were used as a way to consolidate power and maintain control within the royal family. By keeping the bloodline pure, monarchs believed they were preserving their divine right to rule. Marriages between different royal families were often arranged as a way to form strategic alliances and prevent wars. This made marrying a close relative seem like a safer option than marrying someone from another country whose loyalty could be questioned. 

Medicis, Tudors, Romanovs, and even the new blood Bonapartes inter-married with wild abandon. The most tangled of all are the Habsburgs; rulers of Spain, Belgium, the Netherlands, Germany, Prussia, Austria, kind of Hungary, and usually Italy. In 2009 a university in Spain carried out a genetic analysis of the family. Over a two-hundred-year stretch nine out of every eleven marriages (weird numbers, I don’t know why), were between first cousins, uncles, and nieces. Only half of the children recorded to the dynasty survived their first year. At the time the infant survival rate in Spain was averaging 80%. 

The crossed wires of the Habsburgs culminated in the ruin that was Charles II, nicknamed ‘the hexed’ due to his deformities. His mother, Mariana of Austria, had been the niece of his father, King Philip IV. She was also the daughter of Maria Anna of Spain, a Habsburg, and Emperor Ferdinand III of the Holy Roman Empire, another Habsburg. 

The Habsburgs had an heirloom chin which Charles inherited the worst incarnation of. The same feature was credited for Marie Antoinette’s darling pout. Charles, on the other hand, struggled to contain an oversized tongue, couldn’t chew his food, and slobbered when he spoke. Under the hood, his medical records tell of intestinal issues, convulsions, and seizures. His failed marriages carry rumors of premature exports and impotence. He didn’t speak until age four. He couldn’t walk until he was eight. He grew up short, weak, and skinny, and at age thirty he was described as looking like an old man. Bald, senile, dropsy all over. His last years were haunted by frequent hallucinations. He died without heirs at the age of thirty-eight and took the Spanish Habsburg dynasty down with him. 

The legacy of inbreeding can still be seen in some European royal families today, in our own Vaporwave Age, with certain genetic conditions being more prevalent among their members. However, modern medicine has helped to mitigate some of these issues, and there is now a greater emphasis on finding partners outside one’s own family. Nonetheless, in this 2023rd year, most of the living descendants of the old kings continue to be mixed pretty thickly. Nearly all of them have descended from either Queen Victoria or King Christian IX of Denmark.

The recent Queen Elizabeth II was married to Philip, Duke of Ediburgh. 
	+Prince Philip is the son of Prince Andrew of Greece and Denmark and Princess Alice of Battenberg. 
		+Alice’s mother was Victoria of Hesse and by Rhine and was a member of the same paternal line as her grandfather, Alexander of Hesse and by Rhine. 
		+Alice’s paternal uncle, Prince of Batternburg, married Princess Beatrice, daughter of Queen Victoria. 
			+Queen Victoria was the great-great-grandmother of Queen Elizabeth II. 
			+Battenburg and Beatrice begat Victoria Eugenie, who married King Alfonso XIII of Spain. 
				+Alfonso and Victoria Eugenie were the grandparents of King Juan Carlos, who abdicated the Spanish   throne in 2014. 
					+Juan Carlos had married Princess Sophia of Greece and Denmark, whose father was a cousin of Prince Philip, Duke of Edinburgh. Prince Philip’s great-grandfather was King Christian IX of Denmark, who was Queen Elizabeth II’s great-great grandfather. 

In short, the recently deceased queen and the duke were third cousins by Victoria and Albert, fourth cousins once removed by King George II and Queen Charlotte, and are related several more times by the Electress of Hanover, Princess Sophia.

The fallout from this has been expensively obscured. Hidden cousins turn up on occasion. A slip-up on the Burke’s form in 1987 revealed a Nerissa and Katherine Bowes-Lyon, the daughters of Queen Elizabeth’s uncle who had been exiled to an asylum in rural Britain due to their vaguely reported learning disabilities. 

This tradition wasn’t limited to the highest dynasties, nor even to the peerages and regimes. Wealth could be enough if enough was felt to be at stake. Mayer Amschel Rothschild, notorious banker, wrote a will that barred his present and future female descendants from direct inheritance, leaving them with few options among eligible bachelors of the same religion and suitable social stature. The result was four of Mayer’s granddaughters marrying his grandsons and another one marrying an uncle. Between 1824 and 1877, thirty out of thirty-six male descendants married their cousins. 

For the new world, there’s the du Ponts; descendants of Hugonaut wealth, soothsayers of the Louisiana Purchase, and today’s Chemical Neo-Royalty family of Delaware. From the time of their beginnings in America, they had seven generations of cousin marriages. 

“The marriages that I should prefer for our colony would be between cousins. In that way we should be sure of honesty of soul and purity of blood.”

— Pierre Samuel du Pont, 1800. 

Genetic studies on the subject are somewhat sparse. Some of the earliest attempts were undertaken by Charles Darwin, himself the grandson of two first cousins, he also married his own first cousin. After the deaths of a few sickly children and noticing signs of sterility in his surviving offspring, he started growing concerned for his family’s virility. His son added his own research as well. Darwin attempted to study the effects of inbreeding in plants. He got as far as finding a higher rate of negative effects in inbred plants, but apparently nothing all that exciting. His son surveyed the wards of mental hospitals and found only a minority of these were the issues of inbreeding. 

Subsequent research comes mostly from Oxford. A 1960 study found that the consequences of inbreeding are highly dependent on what is called the founder effect. That is, if the first couple passes on a large amount of recessive genetic traits, these will compound and magnify through intermarriage. However, if the first couple passes on a healthy genome, their descendants can get away with it for a while. Eventually, if kept up, the deleterious effects begin to accumulate, and genetic vitality declines. 

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