How mass atrocities end: compendium of 40 case studies

We have just launched a compendium of 40 case studies of mass atrocity endings.

The case studies (look here for an alpha listing of cases) include all cases post-1945, that demonstrate strong evidence of the killing of at least 50,000 civilians or persons rendered hors de combat. The studies focus on the direct killing, expanded to include those who died when under the direct control of perpetrators, whether due to starvation or exposure. The signature condition is the camp, whether a resettlement, forced labor or a POW camp. Throughout, we have attempted to exclude fatalities caused by the generalized conditions produced by a perpetrator’s actions or conditions of armed conflict.

We further limit the cases to those where the threshold of 50,000 deaths was reached within five years (to capture conditions of intensity), although in some cases, the atrocity period endures longer. Onsets are marked by the first year witnessing more than 5,000 such deaths, and endings marked as the final year that reaches this threshold when followed by two consecutive years below that level. Throughout, we sought the most credible minimal number of fatalities.

Unlike some datasets on mass atrocities, we include examples from anti-colonial conflicts, where the primary perpetrators are either state or non-state actors, and both war time and peacetime atrocities.

Each case study is divided into five sections. These include: an introduction; atrocities, discussing the patterns of violence across the atrocities period; fatalities, a discussion of the research surrounding the numbers; endings, describing how the violence ended, in line with our criteria; and coding, explaining how and why we coded the ending. We further provide a list of works cited.

Every case falls into one of three main ending typologies: ‘as planned‘ by the primary perpetrator; defeat of the primary perpetrator; and moderation, in which perpetrators’ goals remain unmet, they are not military defeated, and more moderate policies take hold. We coded for some additional factors, explained below:

Normalization: this often accompanies an ending ‘as planned,’ but not always. We only use it when the regime in power at the onset of atrocities remains in power at the end, and decide to adopt more sustainable policies to manage relations with what often remains an oppressed victim group.

Leadership change: internal politics or coups produce a change of leadership. We note cases both where the change appears to produce an ending and where it seems to signal a decision already made to shift policies.

Defeat by domestic actors: military defeat of the primary perpetrator by actors who emerge from a domestic community.

Defeat by international actors: military defeat of the primary perpetrator by actors who emerge from across international borders.

Moderating influence of domestic actors: pressure from internal sources to alter policies away from mass killing.

Moderating influence of international actors: pressure from external sources to alter policies away from mass killing.

Withdrawal of international forces: when armed forces associated with a state outside of that where the violence is taking place, withdrawal.

Mass popular violence: large-scale popular participation in killing.

Multiple victim groups: this focuses on the logic of why civilians are targeted, not necessarily any inherent character trait of the group.

Initiator not the worst: this allows us to differentiate cases where the period of atrocities began under one primary actor but continued at a higher level under another.

Nonstate actor: we code separately for when non state actors (as organized groups with some sort of chain of command) are the primary or a secondary perpetrator of mass atrocities.

Additional factors that might be of interest are included in the keywords for the cases, such as: independence, resettlement, peacekeepers, and stalemate.

How Mass Atrocities End Compendium of Cases

Bridget Conley is an Associate Research Professor at The Fletcher School, Tufts University, and leads WPF’s research programs on atrocity response and incarceration. She works closely with the Executive Director on project development, fundraising and strategic vision for WPF. Currently, her primary research focus concerns the implications of American mass incarceration for local, national and international policies.

She also leads our program on mass atrocities and was a researcher on the mass starvation program. The author of Memory from the Margins: Ethiopia’s Red Terror Martyrs Memorial Museum (Palgrave 2019); co-editor of Accountability for Starvation: Testing the Limits of the Law (Oxford University Press, 2021), and editor of How Mass Atrocities End: Studies from Guatemala, Burundi, Indonesia, the Sudans, Bosnia-Herzegovina, and Iraq (Cambridge University Press 2016), she has also published on starvation crimes, the 1992 – 1995 war in Bosnia, mass atrocities and genocide, and how museums can engage on human rights issues.

At Fletcher, Prof. Conley teaches ‘Understanding Mass Atrocities’ and ‘Contemporary Critical Theory and International Issues.’ She also teaches undergraduate courses with Tufts University Prison Initiative of Tisch College (TUPIT).

She previously worked as Research Director for the U.S. Holocaust Memorial Museum’s Committee on Conscience, where she led the Museum’s research and projects on contemporary threats of genocide, where she produced multimedia public outreach materials, formulated positions on contemporary threats of genocide, and curated exhibitions.

She received a PhD in Comparative Literature from Binghamton University in 2001. When she is not in the office, she is happiest with her family or on a mountain summit.

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