Looking for history rabbit holes to fall into.
For me it has always been the Bronze Age Collapse - how exactly did almost every major civilization near Greece and Egypt that was thriving in 1200 BCE just collapse or drastically weaken over a span of ~50 years? Related mystery - where did the Sea Peoples, raiders who are proposed to have played a role in the collapse, even come from?
I’m still wondering about the Tomb of Genghis Khan, Nobody knows where Genghis Khan was buried and the people that were there were killed to keep him a secret, to keep where Genghis Khan"s body a secret.