The Second Congo War began in 1998 when Rwanda and Uganda backed rebels against the government of Laurent Kabila (whom they had earlier helped install), drawing in Angola, Zimbabwe, Namibia, and other states along with dozens of local militias in a conflict over territory, resources, and regional security. Fighting and its humanitarian consequences, especially disease and malnutrition among displaced populations, produced what the International Rescue Committee called the world's deadliest conflict since World War II, with a widely cited but contested estimate of 3.3–5.4 million excess deaths between 1998 and 2008. At its peak roughly 2.2–3.4 million people were internally displaced within the DRC, concentrated in the eastern provinces. A 2002-03 peace process formally ended the war, though armed conflict and displacement in eastern DRC have continued intermittently ever since.
Nine African states and numerous rebel and militia groups fought in the Democratic Republic of the Congo following the fall of Mobutu, in what became the deadliest conflict since World War II by some estimates
The DRC's last full census was in 1984, when it counted 30.7 million; UN Population Division estimates put the country at roughly 46-47 million in 1998, so the figure is a projection rather than an enumeration. The International Rescue Committee's mortality surveys estimated 3.9 million excess deaths by 2004 and 5.4 million by 2008, figures later criticised by the Human Security Report Project for their baseline assumptions; displacement peaked at over three million people in 2003.
The International Rescue Committee's mortality surveys produced 5.4 million excess deaths for 1998-2007, of which it attributed only around 350,000 to direct violence and the remainder to disease and malnutrition — a figure very frequently misquoted as a count of people killed. The Human Security Report Project at Simon Fraser University argued the pre-war baseline mortality rate had been set too low for a country with the DRC's development indicators and recalculated the toll to roughly 2.8 million, and under 900,000 using a different baseline; IRC co-author Richard Brennan conceded that insecurity forced assumptions and extrapolations but maintained the findings stand.
The UN Mapping Report on the DRC (2010), ICC judgements against Lubanga, Katanga and Ntaganda, and Human Rights Watch documented massacres including the 'Effacer le tableau' campaign against Mbuti communities, mass rape and sexual slavery, forced labour in mining areas, pillage and village burning, and the abduction and conscription of children into armed groups.
Rwanda, Dem. Rep. Congo, Burundi