The UPRONA, a multi-ethnic unity party led by Prince Louis Rwagasore and the Christian Democratic Party (PDC) became the most prominent organizations throughout Burundi-Urundi. After UPRONA's victory in legislative elections, Prince Rwagasore was assassinated on October 13 in 1961, allegedly with the help of the Belgian colonial administration.
The country claimed independence on July 1, 1962, and legally changed its name from Ruanda-Urundi to Burundi. Mwami Mwambutsa IV was named king. On September 18, 1962, just over two months after declaring independence from Belgium, Burundi joined the United Nations.
Upon Burundi’s independence, a constitutional monarchy was established and both Hutus and Tutsis were represented in parliament. When King Mwambutsa appointed a Tutsi prime minister, the Hutus, who were the majority in parliament, felt cheated. An ensuing attempted coup by the Hutu-dominated police was ruthlessly suppressed by the Army, then led by a Tutsi officer, Captain Michel Micombero. When the next Hutu Prime Minister, Pierre Ngendandumwe, was assassinated in 1965, Hutus engaged in a series of attacks on Tutsi, which the government repressed ruthlessly, fearing the killings of Tutsis by Hutus, who wanted to follow the "Model Rwanda". The Burundi police and military were now brought under the control of the Tutsi.
Mwambutsa was deposed in 1966 by his son, Prince Ntare V, who claimed the throne. That same year, Tutsi Prime Minister Captain Michel Micombero deposed Ntare, abolished the monarchy, and declared the nation a republic, though it was in effect a military regime.
In 1972, an all Hutu organization known as Umugambwe w'Abakozi b'Uburundi or Burundi Workers' Party (UBU) organized and carried out systematic attacks on ethnic Tutsi with the declared intent of annihilating the whole group. The military regime responded with large-scale reprisals targeting Hutus. The total number of casualties was never
