When did racial segregation start?
Possibly when the first Cro Magnon met with Homo Sapiens. It may have been earlier in un-recorded history and perhaps it was much later. It has been around, it is a shamefull part of human socialization, it will exist for a long time, it will never be right or correct or honorable. A few rare societies have avoided segregation and discrimination problems, perhaps another such world will exist in a millineum or two.