Pastels on Mi Teintes paper
From un unknown photographer
Some of the Asian invaders traveled quite rapidly between their own homelands and Europe, absorbing little if any white blood on the way, while others took centuries to make the passage. Even those who did not linger among white or part-white populations often had absorbed some white genes as a result of the slave trade. From the fourth century all the way to the 15th century there was an enormous traffic in white slaves, with millions of Slavs trudging eastward in slave caravans.
Mongolian folds of the eyelids exist on almost all Mongols along with relatively high and pronounced cheekbones. The vast majority of Mongols have black hair and brown eyes, although a certain number of Mongols, particularly the Oirat tribe in western Mongolia tend to exhibit lighter features such as fair skin, blue or green eyes, varying shades of brown hair, and sometimes even red or blonde hair.
While the Mongols who struck in the 13th century passed like lightning from Mongolia to the eastern border of Europe, their ruler, Genghis Khan, was described by contemporaries as having green eyes and reddish hair—undoubtedly a consequence of the slave trade.