Afghan rulers maintained cohesion by making Pashtuns overlords over other ethnicities

Evidence

Nonetheless, history does have consequences for the main characters. At the heart of Hosseini’s book is the legacy of Afghan ethnic inequality and violence that always haunts the relationship of the Pashtun Amir and the Hazara Hassan. Amin Saikal has described how earlier attempts to build an Afghan nation from various ethnicities and a complex system of clan and patronage tended to take on an ethnic coloring. For successive rulers trying to bring together these fissiparous elements, “a modicum of national cohesion was maintained by instituting a single group (Pashtuns) as an overlord vis-à-vis all others.” Amir and Hassan are the direct inheritors of such divisive policies. — Peter Morey, Islamophobia and the Novel, 249