Centuries of inbreeding among European royals caused the deformity

The House of Habsburg produced various Austrian and Spanish kings and queens - and they occupied the throne of the the Holy Roman Empire from 1438-1740.

Habsburg Dynasty: The Inbred Royals Who Ruled Over Europe - WorldAtlas

Royal intermarriage - Wikipedia

History's most famous chin officially linked to centuries of inbreeding

Royal Inbreeding - TV Tropes

Centuries of inbreeding among European royals responsible for famous facial deformities seen in historical paintings

Inbreeding behind facial deformity in one of history's largest royal dynasties, study says

Centuries of inbreeding among European royals caused the deformity known as the 'Habsburg jaw

16 Royals Who Suffered From Hereditary Mutations And Defects Caused By Inbreeding

The Habsburg Jaw: deformity shaped by royal inbreeding

History and genetic diseases

Centuries of inbreeding among European royals caused the deformity known as the 'Habsburg jaw