The earliest known inhabitants of Rwanda were pygmoid hunter-gatherers, ancestral to the modern Twa people who today comprise only 0.25% of the national population. Some 2,000 years ago, agricultural and pastoralist migrants from the west settled in the area.
Oral traditions recall that prior to the 15th century a ruler named Gihanga forged a centralised Rwandan state with similar roots to the Buganda and Bunyoro Empires in neighbouring Uganda. Comprised of a cattle-owning nobility and agriculturist serfdom majority - the precursors respectively of the modern-day Tutsi and Hutu - this powerful state was able to repel all early attempts at European penetration.
Rwanda became a German colony following the 1885 Berlin Conference, although it would be a full decade before a permanent German presence was established there. In 1918, Rwanda was mandated to Belgium, which implemented a system of indirect rule that exploited and intensified the existing divisions between Tutsi and Hutu.