UCDP/PRIO Armed Conflict Dataset v4-2009

Uppsala Conflict Data Program (UCDP) at the Department of Peace and Conflict Research, Uppsala University and Centre for the Study of Civil War at the International Peace Research Institute, Oslo (PRIO) and

This web page offers access to the 1946–2008 UCDP/PRIO Armed Conflict Dataset, structured for quantitative analysis. See Gleditsch et al. (2002) and the codebook for further details. Those interested in narrative information on specific conflicts for the post-Cold War period should consult the Uppsala Conflict Database.

When using the data, please cite Gleditsch et al. (2002), as well as the codebook whenever appropriate. For easy replication, include the version number in all analyses using the dataset. 

Further Information

The dataset is described in Gleditsch et al. (2002). Subsequently, six annual updates have been published in the Journal of Peace Research: in September 2003 (Eriksson et al., 2003); September 2004 (Eriksson & Wallensteen, 2004); September 2005 (Harbom & Wallensteen, 2005); September 2006 (Harbom, Högbladh & Wallensteen, 2006); September 2007 (Harbom & Wallensteen, 2007); and September 2008 (Harbom, Melander & Wallensteen, 2008). The updates include some changes in the data published for previous years, and the database is adjusted accordingly. A complete list of these changes is found in the document Version History and Known Errata. For the record, and for replication purposes, we have preserved copies of previous versions.

Individuals affiliated with an institution that holds a current subscription to JPR can download PDF files with the articles from the electronic subscriptions web page of their library. After three years, all JPR articles also become available in Jstor.

This dataset is a collaborative project between the Department of Peace and Conflict Research at Uppsala University and the Centre for the Study of Civil War at PRIO. Until 2002 the conflict data from Uppsala University had only covered the years from 1989 and onwards. Our joint project extended the armed conflict list back to 1946.

Work on the dataset was supported by The World Bank's Development Economics Research Group as part of its project on The Economics of Civil War, Crime, and Violence. More detailed credits – intellectual as well as financial – can be found in the first footnote of Gleditsch et al. (2002).

The dataset has been widely used since it was first made available, both by researchers and policy makers (e.g. Collier et al., 2003; Miguel et al., 2004; and Wolfson et al., 2004).


Collier, Paul et al., 2003. Breaking the Conflict Trap: Civil War and Development Policy. Oxford: Oxford University Press & Washington, DC: The World Bank.

Eriksson, Mikael; Peter Wallensteen & Margareta Sollenberg, 2003. 'Armed Conflict, 1989–2002', Journal of Peace Research 40(5): 593–607.

Eriksson, Mikael & Peter Wallensteen, 2004. 'Armed Conflict, 1989–2003',  Journal of Peace Research 41(5): 625–636.

Gleditsch, Nils Petter; Peter Wallensteen, Mikael Eriksson, Margareta Sollenberg & Håvard Strand, 2002. ‘Armed Conflict 1946–2001: A New Dataset’, Journal of Peace Research 39(5): 615–637.

Harbom, Lotta; Stina Högbladh & Peter Wallensteen, 2006. 'Armed Conflict and Peace Agreements', Journal of Peace Research 43(5): 617–631.

Harbom, Lotta & Peter Wallensteen,  2005. 'Armed Conflict and Its International Dimensions, 1946–2004', Journal of Peace Research 42(5): 623–635.

Harbom, Lotta & Peter Wallensteen, 2007. 'Armed Conflict, 1989–2006', Journal of Peace Research 44(5): 623–634.

Harbom, Lotta, Erik Melander & Peter Wallensteen, 2008. ' Dyadic Dimensions of Armed Conflict, 1946−2007'  45(5): 697-710.

Miguel, Edward; Shankar Satyanath & Ernest Sergenti 2004. 'Economic Shocks and Civil Conflict: An Instrumental Variables Approach', Journal of Political Economy 112(4): 725–753.

Wolfson, Murray; Zagros Madjd-Sadjadi & Patrick James, 2004. 'Identifying National Types: A Cluster Analysis of Politics, Economics, and Conflict', Journal of Peace Research 41(5): 607–623.