Hutu and 14% of residents in Rwanda and Burundi, respectively. The Twa pygmies, the smallest of the two countries' principal populations, also share language and culture with the Hutu and Tutsi. However, they are distinguished by a considerably shorter stature. The Hutu are believed to have first emigrated to the Great Lake region from West Africa in the great Bantu expansion. Various theories have emerged to explain the purported physical differences between them and their fellow Bantu-speaking neighbors, the Tutsi. One such thesis, largely based on oral tradition, posits that the Tutsi experienced some admixture with or were partially descended from
Ethnic groups in Burundi declared a presidential republic; however peace did not ensue as a result. Even after 1966, the subsequent dictatorial regimes of Michel Micombero (1966–76), Jean-Baptiste Bagaza (1976–87), and Pierre Buyoya (1987–93) were dominated by Tutsi elites which often consciously marginalized and discriminated against the Hutu majority. The first Hutu to become head of state was Melchior Ndadaye in 1993, although he was assassinated shortly after taking power. Ethnic violence peaked in 1972 when 100,000 people, mainly Hutu, were killed by the Tutsi regime in the Burundian Genocide. Twa have also been targeted, specifically in violence directed against the Tutsi with whom