What did "divide and rule" have to do with the genocide in Rwanda?
The genocide that occurred in Rwanda during 1994 had its origins in the extreme animosity that had existed for many years between the country's majority Hutu population and its much smaller but politically powerful Tutsis. Rwanda's colonial masters, mainly Belgium, did what many outside occupiers have done, exploit divisions between ethnic groups. As national borders throughout Africa (and the Middle East) were the product of European colonial administrators, and because those borders rarely reflected the natural divisions between and among tribes, clans and other categories, the seeds of eternal conflict were planted and nurtured by those colonial powers. Rwanda and neighboring Burundi were, in a sense, a microcosm of the continent as a whole, but with the degree of antipathy between ethnic groups running even deeper than in much of the rest of sub-Saharan Africa. Belgium's colonial administrators gave the much numerically-smaller Tutsi minority a disproportionate share of political power, constructing the nation's civil service around the Tutsis to the disadvantage of the Hutu majority. The relationship between the two groups had been violent for many decades, and post-colonial administration by the Tutsis left the Hutu feeling disenfranchised and bitter. When the spark -- the shooting down of the aircraft carrying the presidents of both Rwanda and Burundi -- was lit in 1994, the Hutu exploded in genocidal rage against the Tutsi minority, as well as against moderate Hutus who opposed militant reactions to the events then occurring. The resulting killing spree resulted in around 800,000 deaths.
Now, the Rwandan genocide occurred many years following its independence from Belgium (1961), but the animosities that led to the horrific violence during 1994 had its seeds in that earlier colonial period. European efforts at exploiting divisions among those it colonized played a major role in the protracted period of violent confrontations between Hutus and Tutsis that characterized Rwanda's politics between independence and genocide. In that respect, "divide and rule" was integral to the chain of events that led to the genocide.