The Hapsburgs, a Spanish noble house that held the Spanish throne, made a practice of the inverse of this with uncle-niece marriages to keep power in the house. This was the closest marriage the church would allow. The generations of inbreeding produced the distinct "Hapsburg jaw". Eventually that led to the poor, ugly, absurdly inbred Charles II of Spain. And remember, those portraits are official portraits that paint him in the best possible light. He died without an heir, ending the Hapsburg monarchy.

[–] flop_leash_973@lemmy.world 3 points 4 months ago* (last edited 4 months ago)

It has always been kind of funny to me that the painters of these official portraits had to at some point get directions along the lines of "I want it to be flattering but clearly me" for some of the portraits they had to do of what had to be pretty bridge troll ugly looking people.

Talk about going home that night after getting the assignment, having a stiff drink, and wondering how the hell you are going to get out of this one.