The situation in Rwanda was largely influenced by the incidents in Burundi.Both countries have a Hutu majority, an army in Burundi was controlled by Tutsi. After the assassination of Rwagasore, his UPRONA party was split into two factions,Hutu and tutsi. A tutsi prime minister was chosen by the monarch, but a year laterin 1963,was forced to appoint a Hutu Prime minister. In 1965, Ngendandumwe, a Hutu, the elected prime minister was assasinated by a Tutsi extremist.To avoid controversy, the Mwami appointed his personal secretary,Leopold beha, as prime and immediately, this led to a coup by the Hutus. Ultimately a military rule continued for 27 years in Burundi until the next free election in 1993. In 1988, Hutu violence against Tutsis surfaced in Burundi and in response the Tutsi army massacredapproximately 20,000 more Hutu. and thosands of Hutu exiled into Tanzania and Congo.
In 1986, Yoweri Museveni'sguerilla forces in Uganda had succeded in taking control of the country. Many exiled Rwandan Tutsi refugees had joined this rebel forces and became trained in guerrilla technique.Paul Kagame, a Tutsi and head of military intelligence in Museveni's army, founded the RPF (Rwandan Patriotic Front) to invade Rwanda from Uganda. Kagame had military trainig in USA and in 1991 he broadcasted a radio propaganda from Uganda about RPF.
Some members attached to the military dictatorship of Habyarimina Govt. responded in 1993 about the invasion of RPF and began anti-Tutsi propaganda saying that the Tutsis were trying to enslave the Hutus. However after three years of fighting the Govt. and RPF signed a final ceasefire agreement, known as Arusha accord.But neither of them were agreeable to obey the accord and fighting continued. By that time 1.5 million Hutus had fled away apprehending fresh masscres by the Tutsis on Hutus.
The situation worsened after the assassination of Melchior Ndadaye, a Hutu elected Burudian President by Burudian Tutsi dominated army. In Burundi a fierce civil war was started and tens of thousands, both Hutu and Tutsi were killed. This conflict spilled over to Rwandan border and caused caused the fragile Rwandan Arusha accords to quickly scrumble.