... is estimated to have killed between 30% and 60% of Europe's total population, and between 75 and 200 million people altogether (out of a total world population of 450 million). It's thought to have originated in the plains of Central Asia and travelled along the Silk Road, reaching Crimea by 1343. It was probably carried by Oriental rat fleas living on black rats, which travelled to Europe on merchant ships.
© Haydn Thompson 2017