Among the first known inhabitants of Burundi were the Twa and the Hutu. About the 15th century, the Tutsi migrated into the region from the north. They forced the Hutu and Twa into virtual serfdom and established a feudal monarchy. Burundi remained largely unexplored by Europeans until the 1890's, when it became part of German East Africa. It was taken over by Belgium during World War I and then was made part of Ruanda-Urundi, a League of Nations mandate (later, a United Nations trust territory) under Belgian administration.

In 1962 Burundi achieved independence, becoming a constitutional monarchy under a Tutsi mwami (king). Violent conflict broke out between the Hutu and Tutsi. In 1965, a Hutu rebellion was put down by Tutsi elements in the army. The following year Tutsi army officers overthrew the king and proclaimed a republic. The Hutus rebelled again in 1972; the revolt was brutally suppressed, with some 100,000 Hutus being killed.

Burundi returned to civilian rule in 1974, but the government remained unstable. In 1976 a military group seized control, but civilian rule was restored in 1982. During 1985–86, the government clashed with the Roman Catholic Church, contending the church was supporting Hutu interests. Priests were jailed or expelled and Catholic schools were taken over by the government. In 1987 a military group overthrew the government; priests were freed from jail and Catholic property was returned.

In elections, held in June, 1993, the Hutus won the presidency and control of parliament. In October, the president was killed by Tutsi army officers in a coup, and violence erupted between the Hutus and Tutsis, leaving some 100,000 dead. The coup failed, and the Hutu-dominated government remained in pawer until 1996 when it was overthrown by the military.

In 2000, the government and several rebel groups signed a peace agreement. In 2001, a transitional constitution was adopted, and Buyoya became president of a transitional government. In February, 2005, voters approved a new constitution that guarantees both the Hutu and the Tutsi a certain share of legislative seats, cabinet posts, and military roles. In July, 2005, elections were held for a National Assembly and a Senate. In September, 2006, the government and the only remaining rebel group, the National Liberation Forces (FNL), signed a cease-fire agreement.

In 2007, Burundi joined the East African Community (EAC). The EAC promotes economic and political cooperation among member countries. Members include Kenya, Rwanda, Tanzania, and Uganda.