> [!info] Metadata > * #articleseed/overviewTopic expand this and re-ship it as something up to my new standards. > Someone on r/AskHistorians asked about why students learn about the [the Hapsburgs](https://www.reddit.com/r/AskHistorians/comments/ht1kue/the_hapsburgs_are_famous_for_their_defects_due_to/), but not Egyptian examples of inbreeding. Check out what I learned while sourcing my response and planning an article about creating fictional worlds with inbred dynasties. ## Quick Facts - King Tut had a "juvenile aseptic bone necrosis" which made it hard for him to walk. - Stillbirth was a common consequence of royal inbreeding. - Despite 300 years of inbreeding, the Ptolemys didn't really have any major genetic issues. - Elissa of Tyre (aka Dido) was married to her uncle. - Incan princes often married their sisters. ## Incestuous Dynasties Incestuous dynasties [were common](https://www.nationalgeographic.com/magazine/article/tut-dna-dobbs) in ancient Egypt, Hawaii, the Incan Empire, pre-industrial Thailand, Phoenicia and several African realms. Incestuous European dynasties like the Hapsburgs tended to marry their cousins, whereas more [ancient royal marriages tended to be between siblings](https://www.nature.com/articles/hdy201325). ## Saved By Polygamy While yes, varieties of sibling marriage were common in Egypt, so was polygamy and the [products of incestuous marriages](https://www.jstor.org/stable/644006) were not typically the heir. Marriages between individuals who grew up together young age are [typically sexless](https://academic.oup.com/beheco/article/24/4/842/220309) due to something a type of sibling avoidance called the Westermarck effect.