Wars on Map

The evidence behind the atlas

Sources, coverage and methodology

This is a research release, not a complete record of every war. Historical sources disagree; estimates and geographic approximations are labelled wherever they appear. This page sets out what the data is, how it is handled, and where it is known to be wrong.

Data retrieved 2026-09-11 · article text checked 2026-09-11

The war catalogue

The catalogue is the Correlates of War project’s four war datasets, retained unchanged and normalised into one file. Each original release is recorded below with its version, coverage cutoff, row count and a SHA-256 hash of the file that was read.

ReleaseVersionCovers toRows
interstate 4.0 2007 337
extrastate 4.0 2007 198
nonstate 4.0 2007 62
intrastate 5.1 2014 420

The result is 740 war records. The catalogue follows its source’s inclusion rules, including its battle-death threshold, so it is not a list of every armed conflict. Categories may represent different phases of one wider conflict, and a war coded to several regions is counted in each of them.

Sources
Correlates of War — war datasets and codebooks ↗ Sarkees, M. R. & Wayman, F. W. (2010), Resort to War: 1816–2007. CQ Press Dixon, J. S. & Sarkees, M. R. (2016), A Guide to Intra-State Wars: An Examination of Civil, Regional, and Intercommunal Wars, 1816–2014. CQ Press

Dates and time semantics

Dates describe coded periods of sustained combat, not declarations or treaties. Distinct combat periods within one war are kept separate, and their union controls what the map shows, so a gap in the fighting stays a gap on the timeline.

Unknown days and months keep their original precision rather than being padded to a date the source never gave; the earliest and latest values in the data are search bounds, not asserted dates. Wars still being fought when a release stopped are marked as ongoing at that cutoff, and no activity is projected beyond it. Original war titles are kept as published, so “present” in a title means the release’s cutoff, not today.

One consequence worth knowing: start dates are coded in a single reference frame, so a war can appear to start a day before the event that is conventionally given as its beginning. The catalogue’s start for the Korean War is 24 June 1950; in Korea the attack came before dawn on 25 June.

Positions, and three artefacts

The catalogue records regions, not coordinates. To draw individual wars, this atlas matches each side’s named participants against Natural Earth country centroids and places the record between the two sides, at a single point where only one side resolves, or — where no participant resolves to a modern country at all — as a dashed badge on the source region’s anchor. A side with more than four resolved participants is deliberately left unplaced, because averaging a large coalition produces a point that represents nowhere.

That rule still lets through artefacts, and three of them are worth naming because they affect well-known wars:

  • The American Civil War marker sits in South Dakota. The Confederacy has no modern territory, so the only resolvable participant is the United States, and the marker is that country’s centroid.
  • The Korean War marker sits in northern China, because it is the average of the two resolvable participants on one side rather than a location in Korea.
  • The First World War marker sits in Romania, for the same reason — an average of the Central Powers that the atlas could resolve.

Markers locate records, not wars. Where a war’s position matters, the timeline and the evidence panel are trustworthy and the single marker is not. Regional circles at the zoomed-out level are the source’s broad regions and are not battle sites or territorial boundaries; different releases use different regional definitions, and those are retained rather than crosswalked into a tidier scheme that the data would not support.

The coastline is modern, from Natural Earth. It is reference geography, not a reconstruction of any historical year, and no political borders or zones of control are drawn anywhere.

Sources
Natural Earth — public-domain map data ↗ Correlates of War — war datasets and codebooks ↗

The battle and campaign layers

23 battles and campaigns supplement the catalogue with dated movements. They are curated for this atlas and are not part of the source dataset. Each one links to the historical accounts it was built from, and each movement carries its own source references.

Dates, formations and directions follow those accounts. Coordinates and curves are approximate editorial anchors: they are not surveyed routes, departure ports, ship tracks, flight paths, territorial control boundaries or simulations of speed. Arrow widths are equal because comparable reviewed force figures have not been entered, and unknown strengths are left explicitly unknown rather than guessed.

A year view combines every movement dated within that year, so it shows a sequence rather than a single battlefield snapshot. Use the month and day scales to follow the order of events.

Full notes and sources for all 23 layers are on the battles page.

How the articles are written

The articles follow four rules, which are the reason they read the way they do.

  • Ranges, not midpoints. Where scholarship disagrees about a death toll, both ends are given with the reason for the spread. A single round number in place of a contested range is a fabrication, however convenient.
  • Attribution for every figure. Each section carries its own sources rather than pointing at a bibliography at the foot of the page.
  • Publications rather than plausible links. External URLs are given only for pages this project has checked and uses in its data files. Everything else is cited as a book, paper or official compilation, with author, year and publisher. A reference a reader can find in a library outlasts a link.
  • Limits stated in the text. Where the map cannot honestly show something — the western front in 1916, the Vietnam War, any pre-1816 war — the article says so rather than drawing it anyway.

Full source register

Every figure, date and range in the articles and battle notes traces back to one of these. Institutional and dataset sources are linked; publications are cited in full.

Datasets and institutional sources

Publications

  • Sarkees, M. R. & Wayman, F. W. (2010), Resort to War: 1816–2007. CQ Press
  • Dixon, J. S. & Sarkees, M. R. (2016), A Guide to Intra-State Wars: An Examination of Civil, Regional, and Intercommunal Wars, 1816–2014. CQ Press
  • Overmans, R. (1999), Deutsche militärische Verluste im Zweiten Weltkrieg. Oldenbourg
  • Krivosheev, G. F. (1997), Soviet Casualties and Combat Losses in the Twentieth Century. Greenhill Books
  • Ellman, M. & Maksudov, S. (1994), "Soviet Deaths in the Great Patriotic War: A Note". Europe-Asia Studies 46(4)
  • Hacker, J. D. (2011), "A Census-Based Count of the Civil War Dead". Civil War History 57(4)
  • Obermeyer, Z., Murray, C. J. L. & Gakidou, E. (2008), "Fifty years of violent war deaths from Vietnam to Bosnia". BMJ 336
  • Clodfelter, M. (2017), Warfare and Armed Conflicts: A Statistical Encyclopedia, 4th ed. McFarland
  • White, M. (2011), Atrocitology: Humanity’s 100 Deadliest Achievements. Canongate
  • Tucker, S. C. (ed.) (2010), A Global Chronology of Conflict. ABC-CLIO
  • Durand, J. D. (1960), "The Population Statistics of China, A.D. 2–1953". Population Studies 13(3)
  • Coghlan, B. et al. (2006), "Mortality in the Democratic Republic of Congo: a nationwide survey". The Lancet 367
  • Human Security Report Project (2010), Human Security Report 2009/2010 — The Causes of Peace and the Shrinking Costs of War. Oxford University Press
  • U.S. Department of Defense, Defense Casualty Analysis System — Korean War and Vietnam War casualty summaries
  • National Archives (United States) — Vietnam War U.S. military fatal casualty statistics
  • National D-Day Memorial Foundation — names-based research into Allied fatalities of 6 June 1944
  • Dear, I. C. B. & Foot, M. R. D. (eds.) (1995), The Oxford Companion to the Second World War. Oxford University Press
  • Weinberg, G. L. (1994), A World at Arms: A Global History of World War II. Cambridge University Press
  • Beevor, A. (2012), The Second World War. Weidenfeld & Nicolson
  • Glantz, D. M. & House, J. M. (1995), When Titans Clashed: How the Red Army Stopped Hitler. University Press of Kansas
  • Glantz, D. M. (2001), The Siege of Leningrad 1941–1944: 900 Days of Terror. Cassell
  • Zetterling, N. & Frankson, A. (2000), Kursk 1943: A Statistical Analysis. Frank Cass
  • Frieser, K.-H. (2005), The Blitzkrieg Legend: The 1940 Campaign in the West. Naval Institute Press
  • Zaloga, S. J. (2002), Poland 1939: The Birth of Blitzkrieg. Osprey
  • Parshall, J. & Tully, A. (2005), Shattered Sword: The Untold Story of the Battle of Midway. Potomac Books
  • Prange, G. W., Goldstein, D. M. & Dillon, K. V. (1981), At Dawn We Slept: The Untold Story of Pearl Harbor. McGraw-Hill
  • Cole, H. M. (1965), The Ardennes: Battle of the Bulge. U.S. Army Center of Military History
  • Hastings, M. (1984), Overlord: D-Day and the Battle for Normandy. Michael Joseph
  • Mitter, R. (2013), China’s War with Japan, 1937–1945: The Struggle for Survival. Allen Lane
  • Frank, R. B. (1999), Downfall: The End of the Imperial Japanese Empire. Random House
  • Keegan, J. (1998), The First World War. Hutchinson
  • Strachan, H. (2001), The First World War, Volume I: To Arms. Oxford University Press
  • Sheffield, G. (2001), Forgotten Victory: The First World War — Myths and Realities. Headline
  • Winter, J. M. (1986), The Great War and the British People. Macmillan
  • Suny, R. G. (2015), "They Can Live in the Desert but Nowhere Else": A History of the Armenian Genocide. Princeton University Press
  • Esposito, V. J. & Elting, J. R. (1964), A Military History and Atlas of the Napoleonic Wars. Praeger
  • Chandler, D. G. (1966), The Campaigns of Napoleon. Macmillan
  • Zamoyski, A. (2004), 1812: Napoleon’s Fatal March on Moscow. HarperCollins
  • McPherson, J. M. (1988), Battle Cry of Freedom: The Civil War Era. Oxford University Press
  • Faust, D. G. (2008), This Republic of Suffering: Death and the American Civil War. Knopf
  • Platt, S. R. (2012), Autumn in the Heavenly Kingdom: China, the West, and the Epic Story of the Taiping Civil War. Knopf
  • Wilson, P. H. (2009), Europe’s Tragedy: A History of the Thirty Years War. Allen Lane
  • May, T. (2012), The Mongol Conquests in World History. Reaktion Books
  • Millett, A. R. (2010), The War for Korea, 1950–1951: They Came from the North. University Press of Kansas
  • Cumings, B. (2010), The Korean War: A History. Modern Library
  • Hastings, M. (1987), The Korean War. Michael Joseph
  • Lawrence, M. A. (2008), The Vietnam War: A Concise International History. Oxford University Press
  • Karnow, S. (1983), Vietnam: A History. Viking
  • Hirschman, C., Preston, S. & Vu Manh Loi (1995), "Vietnamese Casualties During the American War: A New Estimate". Population and Development Review 21(4)

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