Conflict Events Worldwide Since 1468BC: Introducing the Historical Conflict Event Dataset

• Author: Charles Miller,K. Shuvo Bakar
• DOI: http://doi.org/10.1177/00220027221119085
• Published date: 01 February 2023
• Date: 01 February 2023
• Subject Matter: Data Set Feature

Data Set Feature

Journal of Conf‌lict Resolution

2023, Vol. 67(2-3) 522–554

© The Author(s) 2022

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DOI: 10.1177/00220027221119085

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Conf‌lict Events Worldwide

Since 1468BC: Introducing the

Historical Conf‌lict Event

Dataset

Charles Miller

1

and K. Shuvo Bakar

2

Abstract

Quantitative datasets of international conf‌lict skew temporally to modern times

and geographically and culturally to the West. Yet post–1815 conf‌licts featuring

Western actors are only a small part of the history of warfare. Many scholars have

bemoaned the potential selection bias which this introduces to studies of the causes

and effects of military conf‌lict, but as yet quantitative datasets which remedy both

these temporal and geographic shortcomings have been lacking. Some datasets have

expanded the scope of existing offerings temporally and others spatially, while

others have attempted to expand both but with an important lack of detail in terms

of location, participants, timing and outcomes. This dataset sets out to remedy the

def‌icit. Using military history’s most extensive encyclopedia of conf‌lict events, we

have created a dataset of conf‌lict events spanning the globe and a timescale from

1468BC to the invasion of Iraq in 2003, complete with precise geographic coor-

dinates, year, participants and outcome. We demonstrate the promise of this data-

set by using it to assess the frequently asserted relationship between conf‌lict history

and economic development, combined with Nordhaus’GECON sub–national

wealth data and historical data on population density from the Netherlands En-

vironmental Agency.

1

Australian National University, Canberra, ACT, Australia

2

School of Public Health, The University of Sydney, NSW, Australia

Corresponding Author:

Charles Miller, School of Politics and International Relations, Australian National University, RSSS Building,

Canberra, ACT 2601, Australia.

Email: charles.miller@anu.edu.au

Keywords

conf‌lict, interstate war, intrastate war, history

Introduction

The Correlates of War (CoW) dataset represented a major advance in the empirical

analysis of international relations (IR). Nonetheless, CoW introduced into IR a par-

ticular geographic and temporal focus which has served to shape both the questions

asked and the answers given in quantitative IR. Two scope limitations in particular

stand out–f‌irst, the temporal limits of the study, which covers only the time period from

the end of the Napoleonic Wars in 1815 onwards, and second, the geographical limits,

with a set of coding rules which stressed British or French diplomatic recognition in the

pre–1945 era as the key criterion for recognition as a member of the international state

system (Sarkees and Wayman 2010). Correlates of War is consequently limited in its

attention primarily to post Westphalian, primarily Western states. As such, CoWallows

analysts to examine only a relatively small slice of the overall history of IR. Many IR

scholars have stressed the potential for selection bias arising from this strongly Euro-

centric focus (Kang 2003), yet CoW’s temporal coverage of European/Western IR

history is also relatively limited. The precise degree of selection bias which this in-

troduces to quantitative IR studies depends of course on the question asked, but it could

in many cases be acute. In addition to selection bias, the temporal and geographic limits

of CoW restrict the range of questions which quantitative IR studies can address. For

instance, theories of IR which see the post–Westphalian state system as the result of a

long–run process of cultural evolution cannot be answered within the CoW framework

which focuses only on the end result of any such process. Other long–run questions

such as the relationship between climate change and conf‌lict, war and the emergence of

the state as the dominant form of political organization and the timing and origins of

Western military hegemony are also hard if not impossible to answer within the

conf‌ines of CoW.

Recent work has both drawn attention to the temporal and geographic narrowness of

the predominant framework in IR, but has not introduced any alternative datasource.

Some new datasets have been produced in IR and economics which attempt to extend

the scope of quantitative studies of conf‌lict temporally and geographically, but none

have attempted to produce a fully comprehensive dataset of worldwide military conf‌lict

throughout history. This dataset seeks to rectify this gap.

Using an Encyclopedia which has been praised by military historians as the most

comprehensive in the literature, we have produced the most spatially and temporally

comprehensive dataset of military encounters to date, covering the entire world back to

1468BC, which we term the Historical Conf‌lict Event Dataset (HCED). Consistent with

the practice embodied in contemporary conf‌lict event datasets such as the Armed

Conf‌lict Location and Event Data (ACLED) project, we gather data on the precise

location of each encounter, along with the war in which the encounter took place, the

Miller and Bakar 523

participants and the outcome. To give an idea of the potential of the dataset, we use it to

test the frequently asserted relationship between warfare and economic development

outside of the early modern European context in which it was f‌irst developed, combining

our data with Nordhaus’G-Econ data on economic development at the sub–national level

and the Netherlands Environmental Assessment Agency’s HYDE data on historical land

use worldwide.

Previous Datasets

Datasets in international conf‌lict generally face a trade–off between temporal and

geographic scope and the degree of detail which can be provided about each conf‌lict.

Conf‌licts which are more recent in time can obviously be covered in much greater detail

than those in the distant past. Similarly, there will be far more detailed source material

on conf‌licts involving high income countries in general and Western countries in

particular. Thus the geographical and temporal skew of existing datasets such as CoWis

to some extent an inevitable result of data availability. However, while it is diff‌icult to

produce the same level of detail on, say, a conf‌lict and its participants in medieval India

relative to World War One, that does not justify excluding conf‌licts of the former type

entirely from IR datasets. Progress can be made by adding what we know now to a

comprehensive dataset, which can always be added to in future as more research and

evidence emerges on the distant past and on the history of conf‌lict outside of the West.

This dataset is intended to be a start rather than the end of a process of expanding the

quantitative study of conf‌lict beyond the relatively recent past and beyond the pre-

dominantly Western international state system.

Modern Era Conf‌lict Datasets –COW, Uppsala Conf‌lict Data Program,

ACLED, Loss Exchange Ratio Dataset, Project Mars, Interstate War Battles

Dataset

Correlates of War remains the industry standard for quantitative IR research. The

Uppsala Conf‌lict Data Program (UCDP) is similarly seminal (Sundberg and Melander

2013). As such, we do not intend to spend much time discussing the specif‌ics of the

dataset. Instead we focus on the differences with our current project.

First, CoW disaggregates its conf‌lict datasets according to conf‌lict type–intra–state,

inter–state, extra–systemic and so forth. The key distinction is whether one or both of

the participants is classif‌ied as a ‘state’in the sense of being represented in the United

Nations or, for the pre–1945 era, whether they were recognized as such by either Britain

or France (Sarkees and Wayman 2010).

For much of the spatio–temporal scope of HCED, however, neither of these coding

rules could work –many of the conf‌licts recorded in HCED occurred long before either

Britain or France even existed in their modern form. An alternative coding scheme

could in principle be devised whereby one could classify state–like polities according to

criteria such as the type of authority relations they embody, but it is not clear whether it

524 Journal of Conf‌lict Resolution 67(2-3)