Tuaregs

The Tuaregs of North Africa are famous as "the Blue Men"; their clothing was blue and they sometimes rubbed indigo dye into their skin as well. But they've been desert dwellers for at least 1500 years; if you're in the desert and you don't want white, you can get black wool or black goat hair, but where do you get indigo blue from? I'm sure you've been laying awake at night, pondering that very question. It turns out that they went south across the desert in caravans to the markets and dye pits of Kano, a city in northern Nigeria.