Nearly every area in the globe was occupied by an earlier group before it was occupied by the present occupying group. Many areas had wave after wave of occupying group, some eliminating the previous group, some merging with the previous group. The people now "Greek" have little relationship to the ancient Greeks, the Mid East is mess, India has fabric of different groups, China was conquered by multiple waves of "barbarians", etc.

Many of these conquests and settlement processes have unspeakably cruel. European process stand out for being the largest and most recent but not necessarily otherwise. The cause for hope is that just hearing all this, most people want something better.