Illustration of the marriage of a close relative of the European royal family
A crown, a ring, a cousin. What else do you need for a royal wedding?
At this point, the fact that so many members of the royal family in history married relatives, now known as close relatives, is somehow a historical joke. But why did they do it in the first place?
Before we get into consanguineous marriages, let's admit that it's not just the royal family that wants to "leave it at home." Pierre-Samuel du Pont, the economist and patriarch of a major manufacturing family, was not afraid to acknowledge his family plan, writing in 1810: "For our colonies, my preferred marriage should be between cousins." In this way, we can guarantee the purity of the soul and the purity of the blood. ”
Marriages of european royal consanguinities affect descendants
Other giants are more discrete, but they usually hold the same view. Bank tycoon Mayer Amschel Rothschild refused to allow his female descendants to inherit his fortune, thus ensuring that his daughters and granddaughters would have to find rich, suitable husbands from their cousins. In fact, they were really married: four pairs of cousins of the Rothschilds, and a pair of uncles and nieces married.
But for members of the royal family, interracial marriage is usually a family tradition, and intermarriage with cousins for generations has consequences. Perhaps the most prominent example is the Spanish Habsburg dynasty, a German royal family that made up one of the major dynasties in Europe from the 15th to the 20th centuries.
Member of the Spanish Habsburg family
Through the intermarriage of members of one branch of the family with members of another branch, the power of the Habsburgs lasted for centuries. (This is clearly their strategy, and their family motto used to be "Bella gerant alii, tu felix Austria nube!") The translation is: let others go to war, you, lucky Austria, get married! They also inherited abnormal genes that eventually ended their families.
The Habsburgs tended to marry their own families, with some external examples of the Jaws of the Habsburgs, which often appear in royal portraits. While incest marriages have long been suspected of being the root cause of these facial deformities, with 9 out of 11 marriages in the 200 years of Habsburg rule being between close relatives, in 2019 they were almost all confirmed to be the culprits.
The chin of the Spanish Habsburg family
When a team of researchers investigated a family's "inbreeding coefficient" (the likelihood that a person would get two identical genes because of their parents' kinship), the average inbreeding coefficient of habsburgs was 0.093, meaning that 9 percent of their maternal and paternal genes were identical. Carlos II, the last Habsburg king, had no offspring due to infertility, and his inbreeding coefficient was 0.254. British envoy Alexander Stanhope described him as "swallowing everything he ate because his jaw was so protruding that two rows of teeth couldn't bite each other." "However, compared to the children of other Habsburg families, Carlos II may be considered very fortunate that he lived to be 39 years old. Although about 80% of Spanish babies at the time were able to survive childhood, only 50% of Habsburg children lived to be 10 years old.
Even though inbreeding coefficients were much lower than those of members of the Habsburg royal family who faced the consequences of interracial marriage, there was a presence that inbreedings caused offspring to suffer terrible diseases. For example, Queen Victoria, the last King of the Hanover dynasty of England, and several descendants of her cousin Prince Albert suffered from hemophilia, a complication that eventually led to the death of one of the couple's children and two or three grandchildren. The suspected suffering of George III, the third monarch of the Hanoverian dynasty in England, may also have been passed down to Victoria's descendants, particularly the Hohenzollern family in Germany, who, in addition to being associated with Victoria, were already descendants of George I. A courtier aptly diagnosed him with "the stain of George III".
In 1840, Queen Victoria married her cousin Prince Albert
Marriages of close relatives were common at the time, and participants did not know what serious consequences their offspring would suffer. And, it is likely that most close relatives marry neither out of love nor out of desire. These royal cousins had a clear purpose: to maintain the power and prestige in the family for as long as possible.