States involved in interstate conflicts

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What you should know about this indicator

'1' indicates that the state participated in a conflict. '0' indicates that the state did not participate in a conflict.

States involved in interstate conflicts
State participated in at least one conflict with another state where force was threatened, displayed, or used that year.
Gibler and Miller - Militarized Interstate Events (2023) – with major processing by Our World in Data
Last updated
September 21, 2023
Date range

Sources and processing

This data is based on the following sources

The MIE data includes daily events data that correspond to the Jones, Bremer, and Singer (1997) coding rules, with some additional coding changes as described in the codebook.

A Militarized Interstate Event (MIE) is a threat, display, or use of force by one state in the Correlates of War (CoW) international system against another state. We faithfully implement the coding rules described in Jones, Bremer and Singer (1996) and the changes to the coding rules made by CoW in the years since. Nevertheless, we also do make several coding rule changes to remove ambiguities in the rules and to provide additional information for researchers.

The changes we make and rationale for them are described well in the manuscript. Of particular note, though, is that we have added an action code labeled "war battle" that describes sustained fights between opposing, organized armed forces. We no longer code "beginning a war" or "join ongoing war" as a militarized action; we only code threats, displays, or uses of force. We code fatality ranges for each event, discarding CoW's use of ordinal fatality scales and the fatality precision variable. This produces minimum and maximum estimated fatalities for each MIE, with no missing values, which can aggregate to meaningful ranges for confrontation-level, confrontation-participant-level, and dyad-year summaries.

Retrieved on
September 21, 2023
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
D. M. Gibler and S. V. Miller, "The Militarized Interstate Events (MIE) Dataset,
1816-2014." Conflict Management and Peace Science. Forthcoming.

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  • All data produced by third-party providers and made available by Our World in Data are subject to the license terms from the original providers. Our work would not be possible without the data providers we rely on, so we ask you to always cite them appropriately (see below). This is crucial to allow data providers to continue doing their work, enhancing, maintaining and updating valuable data.
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How to cite this page

To cite this page overall, including any descriptions, FAQs or explanations of the data authored by Our World in Data, please use the following citation:

“Data Page: States involved in interstate conflicts”, part of the following publication: Bastian Herre, Lucas Rodés-Guirao, Max Roser, Joe Hasell and Bobbie Macdonald (2024) - “War and Peace”. Data adapted from Gibler and Miller. Retrieved from [online resource]
How to cite this data

In-line citationIf you have limited space (e.g. in data visualizations), you can use this abbreviated in-line citation:

Gibler and Miller - Militarized Interstate Events (2023) – with major processing by Our World in Data

Full citation

Gibler and Miller - Militarized Interstate Events (2023) – with major processing by Our World in Data. “States involved in interstate conflicts” [dataset]. Gibler and Miller, “Militarized Interstate Events” [original data]. Retrieved July 18, 2024 from