Chapter 2: Armed conflicts and peace agreements

Conflict data projects

There are several projects that deal with the collection of systematic data and have been influential for the presently important projects. They are valuable to study, to see the development of their definitions, methods of data collection and ways of disseminating their findings. The work presented in Understanding Conflict Resolution departs largely from the Uppsala Conflict Data Program. It can be reached for free use at For the history of this project, see P. Wallensteen 2011. Peace Research: Theory and Practice. London: Routledge. pp. 105–24.

AKUF, Working Group on the Causes of War, University of Hamburg, This is a project that originated in Budapest, Hungary, and now continues from the University of Hamburg, Germany, mostly publishing in the German language for a German public.

The Correlates of War homepage: This is the site of the seminal project that also stimulated quantitative studies in international relations research globally. It was initially led by J. David Singer at the University of Michigan, Ann Arbor, MI, USA. J.D. Singer 1972. ‘The Correlates of War Project’, World Politics, 24: 243–70 introduces the early phases of this project, presents the underlying ideas as well as the hopes for the project.

Q. Wright 1942. A Study of War. Chicago: University of Chicago Press. Many of these data projects explicitly refer to the work of Quincy Wright, and the original study with its many observations and data collections still remains interesting to read. It has a series of appendices that illuminate different, researchable topics. There is a later, abbreviated version of this work.

Comparing conflict data collections

J. Dixon 2009. ‘What Causes Civil Wars? Integrating Quantitative Research Findings’, International Studies Review, 11 (4): 707–35. The author compares sources used by different researchers for the study of civil wars and assesses common findings.

K. Eck 2005. A Beginner’s Guide to Conflict Data. Finding the Right Dataset. Uppsala, Sweden: UCDP Papers No 1, Eck’s overview provides a quick introduction to all the data collections that were known at the time. It still remains a useful guide.

E. Forsberg, A. Duursma and L. Grant 2012. Theoretical and Empirical Considerations in the Study of Ethnicity and Conflict. Uppsala: Uppsala University, UCDP Paper No 8. Download at This work is based on a conference drawing together a number of the leading data collection projects focusing specifically on ethnic conflict.

Trends in armed conflict

The issue of whether wars and violence are in decline has given rise to a number of discussions. It was, in particular, stimulated by the best-selling work of Steven Pinker: S. Pinker 2011. The Better Angels of Our Nature. New York: Viking, and N.P. Gleditsch, S. Pinker, B.A. Thayer, J.S. Levy and W.R. Thompson 2013. ‘The Forum: The Decline of War’, International Studies Review, 15: 396–419. In a forum for discussion, the trend towards a reduction in numbers and fatalities of conflicts was debated at the annual convention of the International Studies Association 2012. Some of the interventions were brought together in this volume, which thus gives an update on the discussions as they stood in the early 2010s. These works all have an expectation that the number and intensity of wars are declining. The continued work of UCDP shows that this is not necessarily the case. In fact, the wars of 2022 resulted in more battle-related deaths, as reported in later UCDP publications, for example, in Journal of Peace Research 2023.

There are surprisingly few statistical studies of how wars end. This makes J. Kreutz 2010. ‘How and When Armed Conflicts End: Introducing the UCDP Conflict Termination Dataset’, Journal of Peace Research, 47 (2): 243–50 a most valuable source. In the sixth edition of Understanding Conflict Resolution Kreutz has graciously provided recent information (see Table 2.1).

As UCDP also collects data on other forms of violence than armed conflict that constitute the focus in this book, its annual articles in JPR now deal with ‘organized violence’. This includes the category of one-sided violence that is discussed in Chapter 12 in this volume of Understanding Conflict Resolution. A recent publication brings this together: Shawn Davies, Therése Pettersson and Magnus Öberg 2022. ‘Organized Violence 1946–2021 and Drone Warfare’, Journal of Peace Research, 59 (4): 593–610.

Peace agreement data

An important novel development is the emergence of dataset entirely devoted to peace agreements. The projects mentioned here all focus on the post-Cold War period. UCDP has such information, as mentioned in this chapter, and used throughout this volume. In addition, there is PAM, the Peace Accords Matrix of the Kroc Institute, University of Notre Dame, including practical considerations and deep information on agreements, such as that provided by UCDP. PAM focuses on the implementation of ‘comprehensive peace agreements’ during their first ten years. The Barometer project is engaged in the monitoring of the 2016 Colombia peace agreement and emerged from PAM (see Chapter 6 in Understanding Conflict Resolution). Madhav Joshi and John Darby present PAM in ‘Introducing the Peace Accords Matrix (PAM): A Database of Comprehensive Peace Agreements and Their Implementation, 1989–2007’, Peacebuilding, 1 (2): 256–74 from 2013.

A different peace agreement data project is PA-X, based at University of Edinburgh, including more than 1959 agreements in around 150 peace processes (as of April 2022) concluded by actors in conflicts with armed violence causing more than 25 conflict-related deaths in one year. It has a particular focus on gender, something useful for Chapter 12: Christine Bell, Sanja Badanjak, Robert Forster, Astrid Jamar, Jan Pospisil and Laura Wise 2017. PA-X Codebook, Version 1. Political Settlements Research Programme, University of Edinburgh, Edinburgh.

Interpretations of conflict information

Of course, data are still open to interpretation. The facts provided by the data projects create a framework for understanding, but may also lead to a quest for different ways of collecting information. Two significant contributions are provided by Ann Tickner and Idean Salehyan, relating this to gender studies and climate change research, respectively: Ann J. Tickner 1997. ‘You Just Don’t Understand: Troubled Engagements Between Feminists and IR Theorists’, International Studies Quarterly, 41 (4): 611–32 and Idean Salehyan 2014. ‘Climate Change and Conflict. Making Sense of Disparate Findings’, Political Geography 43 (2014):1–5.

There are also efforts attempting to integrate different data sets, to understand particular conflicts more fully. An example is K. Donnay, E. T. Dunford, E. C. McGrath, D. Backer, and D.E. Cunningham 2019. ‘Integrating Conflict Event Data’, Journal of Conflict Resolution63 (5): 1337–64.

Conflict data can also be used for the study of the effects of armed conflict and war on social conditions and mental health. An example is Ayesha Kadir, Sherry Shenoda and Jeffrey Goldhagen 2019. ‘Effects of Armed Conflict on Child Health and Development: A Systematic Review’, PLOS ONE 14(2): e0212393.