Succession can mean something that "follows". I'm suggesting here a definition in relation to Darfur and the Sudan as having a very long history of successive rulers or conquerers. In the case of the "Fur" tribe of Darfur, their history is long and complex but it is really only in the last two decades that the ruling government has engaged in a campaign of extermination against them. Prior to this their culture has always, for the most part, been preserved, despite successive rule.