thumb|right|Maasai man Many ethnic groups that had already formed settlements in the region were forcibly displaced by the incoming Maasai. Other, mainly Southern Cushitic groups, were assimilated into Maasai society. The Nilotic ancestors of the Kalenjin likewise absorbed some early Cushitic populations.
thumb|right|maasai man many ethnic groups that had already formed settlements in the region were forcibly displaced by the incoming maasai other mainly southern cushitic groups were assimilated into maasai society the nilotic ancestors of the kalenjin likewise absorbed some early cushitic populations