Most inbred royalty?


Ad Honorem
Dec 2015
Was Inbreeding one of the major reasons behind ultra-high child mortality rate (or incidents) among European royalties?


Ad Honorem
Jun 2013
Purely in terms of phenotypes (expressed genetic traits), can you really beat Charles II of Spain?

His family tree features no less than 11 marriages to blood relatives (consanguineous), and it seems like in the toss of the Hapsburg genetic dice, Charles II got all of the less desirable / dysfunctional genes.

The notes taken at his autopsy were bizarre.
"He continuously baffled Christendom by continuing to live"
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Jan 2008
The Portuguese royal family was also very inbred in the late 1700s and early 1800s.

King Jose I (1714-1777) , who had no sons, decided to marry his eldest daughter Maria to his younger brother Pedro. Portugal didn't go by Salic law, and Maria was Jose's official successor, but the king evidently hoped to perpetuate the agnatic Braganza dynasty in Portugal by marrying his daughter to her uncle. The marriage appeared to be quite successful, and produced 2 young princes. Jose and Joao.

However, old King Jose apparently became a bit carried away with his penchant for match-making within the family. He still had 3 spinster daughters (Maria's younger sisters). He arranged for the youngest one, Benedita, to marry his grandson Prince Jose. Prince Jose was 15 years old when he was married to his 30 year old Aunt Princess Benedita. Old King Jose passed away 3 days after the wedding he'd arranged took place, so hopefully he died happy. King Jose was succeeded by his daughter, who became Regnant Queen Maria I of Portugal, and her uncle/husband became King-Consort Pedro III. Prince Jose was the heir-apparent.

Evidently young Jose's marriage to his wife/aunt Benedita was quite happy, though they (probably fortunately) had no surviving children. (Benedita reportedly had 2 miscarriages.) At the age of 27, Jose contracted smallpox and died. Although Benedita lived to the advanced age of 83, she declined to ever marry again.

Queen Maria, who was known for her rather extreme piety and religious observances, eventually lost her mind by 1786, and in 1792 she was declared insane. She'd been predeceased by her husband/uncle Pedro. She herself died in 1816 in Brazil, where the royal family was then living in exile. She was succeeded by her surviving second son, who became King Joao VI.

King Joao broke with family tradition, and sought a bride outside of his immediate family. He married Spanish Princess Carlotta Joaquina. Joao and Carlotta Joaquina were both renowned for their great ugliness, nor did they get along well with each other, yet they raised a large family of 9 exceptionally good-looking children, and were the ancestors of the later Portuguese and Brazilian royal families.
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Ad Honorem
Jan 2017
Republika Srpska
There was also inbreeding among the Hawaiian royalty. King Kamehameha II married a number of his half-sisters and it is possible that Kamehameha I's wife Peleuli was his full sister.
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