It all started in a poor, kleptocratic state called Zaireball, ruled by Mobutu Sese Seko. he got into power by killing socialist prime minister Patrice Lumuba in a coup backed by Belgiumball and the CIA. Mobutu was evil as hell and was willing to silence opponents, but because many of his views were anti-communist such as supporting the Portuguese in Angolaball (and as said helping killing Patrice, who was a socialist), USAball and South Africaball were willing to support Zaireball for the rest of the Cold War.
In Rwandaball'a clay however, the Tutsis felt oppressed by the Hutu government and started to rebel. As a result, this led to a horrible event; the Rwandan Genocide
OMG CAN PEOPLE STOP BRINGING IT UP FOR 3 SECODNS WHEVER THEY TALK ABOUT RWANDA. This led to many tutsis fleeing to Zaireball. Hutu extremists, ALIRball and Interahamweball also fled to Zaire, and used refugee camps to try to build a coalition to invade Rwanda.
To reduce a rebellion by the Tutsis, Zaireball started supporting the Hutus to kill the Tutsis in its clay. But this only made Rwandaball pissed off, because the Rwandan Civil War ended and the Tutsi government led by Paul Kagame ruled the country to this day. Now that the Tutsis, have the higher ground in Rwanda, they started giving weapons those of the Tutsi who fled to Zairian lands. They eventually invaded Zaireball with the help of Ugandaball & Burundiball, all three of which which Mobutu had supported opposition groups against.
Congolese Laurent Kabilia believed that by sibing with the invaders and rebels, he can end Zaireball, bring a democratic state, and improve living conditions in the Congo. Well, Zaireball's dictator had been dying anyways. Alliance of Democratic Forces for the Liberation of Congoball was created and operated in the eastern portion of Zaireball, and overtime, the more the war went on the more territory Kabilia helped foreign invaders seize. Zaireball had to rely on mercenaries from around many countries in Africa with some from Europe, with the promise of giving them access to African resources. The White Legionball was made up with former Yugoslaviaball for example, defended Kisangani until it fell.
Months after, Angolaball started sending troops near the capital.