How to destroy an empire: Inbreeding

The study, published this week in the journal Public Library of Science One, indicated that Charles II suffered from two separate rare genetic conditions, which were almost certainly the result of his ancestors’ marriage patterns and which effectively assured that the dynasty died out with him.

Nicknamed El Hechizado (“the hexed”) because of his deformities, Charles II was not only inflicted with an extreme version of the Hapsburg chin, as immortalised in portraits by Titian and Velazquez, but his tongue was said to be so big for his mouth that he had difficulty speaking and drooled.

Historical accounts record that he also suffered from an oversized head, intestinal upsets, convulsions and, according to his first wife, premature ejaculation and his second wife, impotence.