The American Civil War is the conflict with the largest number of American military fatalities in history. In fact, the Civil War's death toll is comparable to all other major wars combined, the deadliest of which were the World Wars, which have a combined death toll of more than 520,000 American fatalities. The ongoing series of conflicts and interventions in the Middle East and North Africa, collectively referred to as the War on Terror in the west, has a combined death toll of more than 7,000 for the U.S. military since 2001. Other records In terms of the number of deaths per day, the American Civil War is still at the top, with an average of 425 deaths per day, while the First and Second World Wars have averages of roughly 100 and 200 fatalities per day respectively. Technically, the costliest battle in U.S. military history was the Battle of Elsenborn Ridge, which was a part of the Battle of the Bulge in the Second World War, and saw upwards of 5,000 deaths over 10 days. However, the Battle of Gettysburg had more military fatalities of American soldiers, with almost 3,200 Union deaths and over 3,900 Confederate deaths, giving a combined total of more than 7,000. The Battle of Antietam is viewed as the bloodiest day in American military history, with over 3,600 combined fatalities and almost 23,000 total casualties on September 17, 1862. Revised Civil War figures For more than a century, the total death toll of the American Civil War was generally accepted to be around 620,000, a number which was first proposed by Union historians William F. Fox and Thomas L. Livermore in 1888. This number was calculated by using enlistment figures, battle reports, and census data, however many prominent historians since then have thought the number should be higher. In 2011, historian J. David Hacker conducted further investigations and claimed that the number was closer to 750,000 (and possibly as high as 850,000). While many Civil War historians agree that this is possible, and even likely, obtaining consistently accurate figures has proven to be impossible until now; both sides were poor at keeping detailed records throughout the war, and much of the Confederacy's records were lost by the war's end. Many Confederate widows also did not register their husbands death with the authorities, as they would have then been ineligible for benefits.

Estimates for the total death count of the Second World War generally range somewhere between 70 and 85 million people. The Soviet Union suffered the highest number of fatalities of any single nation, with estimates mostly falling between 22 and 27 million deaths. China then suffered the second greatest, at around 20 million, although these figures are less certain and often overlap with the Chinese Civil War. Over 80 percent of all deaths were of those from Allied countries, and the majority of these were civilians. In contrast, 15 to 20 percent were among the Axis powers, and the majority of these were military deaths, as shown in the death ratios of Germany and Japan. Civilian deaths and atrocities It is believed that 60 to 67 percent of all deaths were civilian fatalities, largely resulting from war-related famine or disease, and war crimes or atrocities. Systematic genocide, extermination campaigns, and forced labor, particularly by the Germans, Japanese, and Soviets, led to the deaths of millions. In this regard, Nazi activities alone resulted in 17 million deaths, including six million Jews in what is now known as The Holocaust. Not only was the scale of the conflict larger than any that had come before, but the nature of and reasoning behind this loss make the Second World War stand out as one of the most devastating and cruelest conflicts in history. Problems with these statistics Although the war is considered by many to be the defining event of the 20th century, exact figures for death tolls have proven impossible to determine, for a variety of reasons. Countries such as the U.S. have fairly consistent estimates due to preserved military records and comparatively few civilian casualties, although figures still vary by source. For most of Europe, records are less accurate. Border fluctuations and the upheaval of the interwar period mean that pre-war records were already poor or non-existent for many regions. The rapid and chaotic nature of the war then meant that deaths could not be accurately recorded at the time, and mass displacement or forced relocation resulted in the deaths of many civilians outside of their homeland, which makes country-specific figures more difficult to find. Early estimates of the war’s fatalities were also taken at face value and formed the basis of many historical works; these were often very inaccurate, but the validity of the source means that the figures continue to be cited today, despite contrary evidence.

In comparison to Europe, estimate ranges are often greater across Asia, where populations were larger but pre-war data was in short supply. Many of the Asian countries with high death tolls were European colonies, and the actions of authorities in the metropoles, such as the diversion of resources from Asia to Europe, led to millions of deaths through famine and disease. Additionally, over one million African soldiers were drafted into Europe’s armies during the war, yet individual statistics are unavailable for most of these colonies or successor states (notably Algeria and Libya). Thousands of Asian and African military deaths went unrecorded or are included with European or Japanese figures, and there are no reliable figures for deaths of millions from countries across North Africa or East Asia. Additionally, many concentration camp records were destroyed, and such records in Africa and Asia were even sparser than in Europe. While the Second World War is one of the most studied academic topics of the past century, it is unlikely that we will ever have a clear number for the lives lost in the conflict.

Between 2003 and 2024, the annual number of civilian deaths due to the Iraq war has fluctuated significantly. As of July, there were 210 deaths in 2024. Civilian Deaths in the Iraq WarCivilian casualties are the deaths of non-military individuals as a result of military operations. The number of documented civilian deaths in the Iraq war peaked in 2006 at 29,526 casualties. Since then, the number had fallen to 4,162 casualties documented in the year 2011, and the number of casualties has been decreasing again since 2014. Due to the nature of the Iraq war and of war reporting, data cannot be considered exact. Many civilian deaths that occurred during the war in Iraq may remain unaccounted for. The Iraq war was launched in March 2003 upon the invasion of Iraq by U.S. forces. Eight years later, in December 2011, the U.S. formally declared an end to the Iraq war. From the start of the war in 2003 until September 30, 2015, it is estimated that the United States spent a total of over 819 billion US dollars on war costs in Iraq. This number includes funding requested by the President and appropriated by Congress, and accounts for both military and non-military spending. Spending was highest in 2008, that year over 142 billion US dollars were spent in Iraq by the United States government. As of 2022, around 6,561 U.S. active-duty military personnel were deployed in North Africa, the Near East, and South Asia. The number of US American soldiers killed in Iraq peaked in 2007 with just over nine hundred causalities. In the same year, there were over 25,000 civilian deaths in Iraq.

The First World War saw the mobilization of more than 65 million soldiers, and the deaths of almost 15 million soldiers and civilians combined. Approximately 8.8 million of these deaths were of military personnel, while six million civilians died as a direct result of the war; mostly through hunger, disease and genocide. The German army suffered the highest number of military losses, totaling at more than two million men. Turkey had the highest civilian death count, largely due to the mass extermination of Armenians, as well as Greeks and Assyrians. Varying estimates suggest that Russia may have suffered the highest number of military and total fatalities in the First World War. However, this is complicated by the subsequent Russian Civil War and Russia's total specific to the First World War remains unclear to this day.

Proportional deaths In 1914, Central and Eastern Europe was largely divided between the empires of Austria-Hungary, Germany and Russia, while the smaller Balkan states had only emerged in prior decades with the decline of the Ottoman Empire. For these reasons, the major powers in the east were able to mobilize millions of men from across their territories, as Britain and France did with their own overseas colonies, and were able to utilize their superior manpower to rotate and replace soldiers, whereas smaller nations did not have this luxury. For example, total military losses for Romania and Serbia are around 12 percent of Germany's total military losses; however, as a share of their total mobilized forces these countries lost roughly 33 percent of their armies, compared to Germany's 15 percent mortality rate. The average mortality rate of all deployed soldiers in the war was around 14 percent.

Unclarity in the totals Despite ending over a century ago, the total number of deaths resulting from the First World War remains unclear. The impact of the Influenza pandemic of 1918, as well as various classifications of when or why fatalities occurred, has resulted in varying totals with differences ranging in the millions. Parallel conflicts, particularly the Russian Civil War, have also made it extremely difficult to define which conflicts the fatalities should be attributed to. Since 2012, the totals given by Hirschfeld et al in Brill's Encyclopedia of the First World War have been viewed by many in the historical community as the most reliable figures on the subject.

The UCDP, Uppsala Conflict Data Program, contains information on a large number data on organised violence, armed violence, and peacemaking. There is information from 1946 up to today, and the datasets are updated continuously. The data can be downloaded for free.

The UCDP Battle-Related Deaths Dataset is a conflict-year and dyad-year dataset with information on the number of battle-related deaths in the conflicts from 1989-2013 that appear in the UCDP/PRIO Armed Conflict Dataset.

Purpose:

The Uppsala Conflict Data Program (UCDP) collects information on a large number of aspects of armed violence since 1946.

Cite as: UCDP Battle-Related Deaths Dataset v.5-2013, Uppsala Conflict Data Program, www.ucdp.uu.se, Uppsala University

The Office of the United Nations High Commissioner for Human Rights (OHCHR) verified a total of 41,783 civilian casualties during Russia's invasion of Ukraine as of January 31, 2025. Of them, 29,178 people were reported to have been injured. However, OHCHR specified that the real numbers could be higher. How many people have died during the war in Ukraine? OHCHR has estimated the number of deaths of civilians, or non-armed individuals, in Ukraine at 12,605 since the start of the war on February 24, 2022. The highest death toll was recorded in March 2022, at over 3,900. The figures on soldier deaths are reported by Russia and Ukraine’s governmental authorities, but they cannot be verified at this point and thus need to be taken with caution. Conflict-related deaths in Ukraine from 2014 to 2021 After Russia annexed Crimea in 2014, Ukraine has seen a military conflict between the government and the Russia-supported separatist regions of Donetsk and Luhansk. OHCHR estimates that between 14,200 and 14,400 people, including civilians and military personnel, were killed in relation to that conflict from April 14, 2014, to December 31, 2021. Of them, at least 3,400 were civilians.

The United States military entered the Korean War in July 1950 and fought on the side of South Korea against the communist forces of North Korea and the People's Republic of China until August 1953. In total, the United States military would suffer almost 37,000 deaths through hostilities. Of these, servicemembers in the Army made up the vast majority of deaths (82.19 percent), with most of these being the result of soldiers being killed in action. A smaller number of marines and navy servicemembers were killed in Korea, with the majority also having been killed in action for these groups. For the United States Air Force, the composition of total deaths is quite different, as the majority of pilots killed during the conflict were declared dead after going missing in action. This likely reflects the fact that when an airplane was shot from the sky in battle, the remains of the pilots are not recoverable.

Central African Republic CF: Battle-Related Deaths: Number of People data was reported at 261.000 Person in 2023. This records a decrease from the previous number of 675.000 Person for 2022. Central African Republic CF: Battle-Related Deaths: Number of People data is updated yearly, averaging 88.000 Person from Dec 2001 (Median) to 2023, with 17 observations. The data reached an all-time high of 906.000 Person in 2021 and a record low of 27.000 Person in 2015. Central African Republic CF: Battle-Related Deaths: Number of People data remains active status in CEIC and is reported by World Bank. The data is categorized under Global Database’s Central African Republic – Table CF.World Bank.WDI: Population and Urbanization Statistics. Battle-related deaths are deaths in battle-related conflicts between warring parties in the conflict dyad (two conflict units that are parties to a conflict). Typically, battle-related deaths occur in warfare involving the armed forces of the warring parties. This includes traditional battlefield fighting, guerrilla activities, and all kinds of bombardments of military units, cities, and villages, etc. The targets are usually the military itself and its installations or state institutions and state representatives, but there is often substantial collateral damage in the form of civilians being killed in crossfire, in indiscriminate bombings, etc. All deaths--military as well as civilian--incurred in such situations, are counted as battle-related deaths.;Uppsala Conflict Data Program, http://www.pcr.uu.se/research/ucdp/.;Sum;

Afghanistan Battle-Related Deaths: Number of People data was reported at 230.000 Person in 2024. This records a decrease from the previous number of 917.000 Person for 2023. Afghanistan Battle-Related Deaths: Number of People data is updated yearly, averaging 5,552.000 Person from Mar 1990 (Median) to 2024, with 35 observations. The data reached an all-time high of 35,787.000 Person in 2022 and a record low of 230.000 Person in 2024. Afghanistan Battle-Related Deaths: Number of People data remains active status in CEIC and is reported by World Bank. The data is categorized under Global Database’s Afghanistan – Table AF.World Bank.WDI: Population and Urbanization Statistics. Battle-related deaths are deaths in battle-related conflicts between warring parties in the conflict dyad (two conflict units that are parties to a conflict). Typically, battle-related deaths occur in warfare involving the armed forces of the warring parties. This includes traditional battlefield fighting, guerrilla activities, and all kinds of bombardments of military units, cities, and villages, etc. The targets are usually the military itself and its installations or state institutions and state representatives, but there is often substantial collateral damage in the form of civilians being killed in crossfire, in indiscriminate bombings, etc. All deaths--military as well as civilian--incurred in such situations, are counted as battle-related deaths.;Uppsala Conflict Data Program, http://www.pcr.uu.se/research/ucdp/.;Sum;

No. of Deaths: Caused by: Legal Intervention & Operations of War & Aftermath data was reported at 4.000 Person in Sep 2024. This records an increase from the previous number of 2.000 Person for Mar 2024. No. of Deaths: Caused by: Legal Intervention & Operations of War & Aftermath data is updated quarterly, averaging 6.000 Person from Mar 2017 (Median) to Sep 2024, with 21 observations. The data reached an all-time high of 31.000 Person in Jun 2018 and a record low of 1.000 Person in Jun 2020. No. of Deaths: Caused by: Legal Intervention & Operations of War & Aftermath data remains active status in CEIC and is reported by National Administrative Department of Statistics. The data is categorized under Global Database’s Colombia – Table CO.G012: Number of Deaths: Cause of Death.

This dataset is about book subjects and is filtered where the books is Secret casualties of World War Two : uncovering the civilian deaths from friendly fire, featuring 10 columns including authors, average publication date, book publishers, book subject, and books. The preview is ordered by number of books (descending).

It is estimated that the Second World War was responsible for the deaths of approximately 3.76 percent of the world's population between 1939 and 1945. In 2022, where the world's population reached eight billion, this would be equal to the death of around 300 million people.

The region that experienced the largest loss of life relative to its population was the South Seas Mandate - these were former-German territories given to the Empire of Japan through the Treaty of Versailles following WWI, and they make up much of the present-day countries of the Marshall Islands, Micronesia, the Northern Mariana Islands (U.S. territory), and Palau. Due to the location and strategic importance of these islands, they were used by the Japanese as launching pads for their attacks on Pearl Harbor and in the South Pacific, while they were also taken as part of the Allies' island-hopping strategy in their counteroffensive against Japan. This came at a heavy cost for the local populations, a large share of whom were Japanese settlers who had moved there in the 1920s and 1930s. Exact figures for both pre-war populations and wartime losses fluctuate by source, however civilian losses in these islands were extremely high as the Japanese defenses resorted to more extreme measures in the war's final phase.

Here you will find an open data set with the Labour Inspection Authority’s statistics on occupational injury deaths per year for the last five-year period. The Working Environment Act & 5-2 requires employers to notify the Labour Inspection Authority of serious work-related personal injuries to their own employees. Occupational injury death means a work injury that causes the injured employee to die within one year of the accident. The Labour Inspection Authority provides statistics on occupational injury deaths occurring within the Labour Inspection Authority’s administrative area that is limited to the land-based labour market in Norway. Occupational injury deaths in aviation, shipping, fishing and capture, petroleum activities on the Norwegian continental shelf and the construction and operation of land-based petroleum facilities are followed up by other supervisory authorities. Occupational injury deaths in these industries are therefore not included in these statistics. Occupational injury deaths in military occupations are included, with the exception of deaths in war situations. For more information about the data set read here. The open data set consists of: Year (Ar), Monthly name (Maned), Number of occupational injury deaths (Number)

Here you will find an open data set with the Labour Inspection Authority’s statistics on occupational injury deaths per year for the last five-year period. The Working Environment Act & 5-2 requires employers to notify the Labour Inspection Authority of serious work-related personal injuries to their own employees. Occupational injury death means a work injury that causes the injured employee to die within one year of the accident. The Labour Inspection Authority provides statistics on occupational injury deaths occurring within the Labour Inspection Authority’s administrative area that is limited to the land-based labour market in Norway. Occupational injury deaths in aviation, shipping, fishing and capture, petroleum activities on the Norwegian continental shelf and the construction and operation of land-based petroleum facilities are followed up by other supervisory authorities. Occupational injury deaths in these industries are therefore not included in these statistics. Occupational injury deaths in military occupations are included, with the exception of deaths in war situations. For more information about the data set read here. The open data set consists of: Year (Ar), main industry area (Main year), Number of occupational injury deaths (Number)

Causes of deaths among veterans of the 1990/1991 Gulf Conflict

Source agency: Defence

Designation: National Statistics

Language: English

Alternative title: Gulf Veterans: Causes of Death

The 20th century marked a new trend in the recording of war fatalities, where more attention was given to the impact of conflicts on civilian populations, and not just the military. During the Second World War, the extent of the atrocities committed, the large-scale bombing campaigns, and the various famines resulting from the war meant that the scope of the civilian death toll took place was unprecedented - the likes of which had never been seen before, or since. Almost two thirds of all deaths due to the Second World War were of civilians, yet the ratio of military to civilian deaths varied greatly by country. Many British dominions and the United States suffered little to no civilian deaths as they were not located in an active theater of war - civilian fatalities largely came from naval or aerial attacks (such as at Pearl Harbor). In contrast, there were several European colonies in the Asia-Pacific region where all, or at least 95 percent, of total fatalities were among civilians - some of these regions suffered millions of deaths due to famine and atrocities.

This is the first attempt to record the Jewish soldiers who became casualties in the numerous Wars between the Habsburg Monarchy and Revolutionary and Napoleonic France. Jewish military service in the Austrian and Austro-Hungarian army from the mid-19th century onwards, especially during the First World War, is well known and documented. By contrast, nothing comparable has been done for the very first Jewish soldiers in modern history. The time has come to set the record straight!

The current database was compiled from the personal records of the War Archive (Kriegsarchiv) of the Austrian State Archives. At that time, the Habsburg army did not publish casualty lists other than mentioning the names of the most senior officers. To find individual Jewish soldiers who became casualties, one must identify serving Jewish soldiers in the regular musters and revision papers. Those found so far can be seen in the database Jewish Soldiers of the Habsburg Army (1788-1820), which should be used in parallel with this one. The current database offers an outtake with a separate list of Jewish soldiers who were killed, wounded, missing in action, or taken prisoner. The first version has 253 entries. These are arranged chronologically based on the date the soldier first became a casualty. The name of the battle or the action shows at the top of the table. Under each such action, up to four sub-categories are given:

1. K/KIA (Killed in Action) – Soldier killed outright in combat. Readers might be surprised how few such cases appear in the database. There are several possible reasons. Firstly, since 1781 the Habsburg manpower reports began to omit the rubric Vor Feind geblieben (left in front of the enemy) denoting soldiers killed in battle. This was part of a broader rationalisation of military records in the early days of Joseph II’s rule. Whichever was the cause of their death, all fatalities were now perceived as irrecoverable manpower wastage. Soldiers who died in service were now simply marked as gestorben. Identifying combat deaths is only possible by looking at monthly reports called Standes- und Diensttabellen. Even then, the number of combat deaths remains extraordinarily low. It appears that the Habsburg army formally recorded a soldier as ‘killed in action’ only if the body was identified. For this to happen, the army had to remain in control of the battlefield – in other words, the battle had to be won. For much of the Revolutionary and Napoleonic period, this was rarely the case on the Austrian side. It appears that most combat deaths in the period landed in the rubric as ‘missing-in-action’.

2. W/WIA (Wounded in Action) – Muster rolls did not record wounds at all. Monthly tables did so very rarely. The latter were intended primarily as financial documents to record the source of the men’s pay. When a soldier entered hospital, his pay was issued from the hospital fund whose accounts were later reimbursed by the man’s regiment. While dates of hospitalisation were meticulously recorded, the cause of hospitalisation was not mentioned. In most cases, identifying wounded soldiers can only be done indirectly. When dozens or hundreds of men from the same unit were hospitalised on the same day directly after a major battle, it can be reasonably assumed that these were combat casualties. A sure way of identifying a wounded soldier was through the medical evaluation papers (Superarbitrierungs-Liste), which were filed for men no longer fit for wartime service. These papers always mentioned combat wounds, as this was a major argument in favour of making the soldier eligible for admission into the invalids. Unfortunately, the survival rate of these documents is variable and the majority simply do not exist. This database employs two categories for wounded soldiers. When medical papers or hospitalisation date allows clear identification, a soldier is entered into the database as a certain case. When broader context allows (such as wartime service and numerous other hospitalisations from the same company on the same day, suggesting a skirmish), such men are entered as probable cases.

3. P/POW (Prisoner of War) – Unlike the previous two rubrics, the Habsburg military records usually mentioned soldiers taken prisoner (Kriegsgefangen/ In Kriegsgefangenschaft gefallen). The reason was again financial. Firstly, returning men had to be issued with backpay. Secondly, from the Third Coalition War onwards, reciprocal wartime prisoner swaps (Cartel) were discontinued, but the system remained in place to ensure that mutual settlement of accounts between two belligerent armies could happen after the war. This is not the only reason why prisoners make the largest single category in our database. For much of the Revolutionary and Napoleonic period, entire Austrian army corps were forced to surrender (for instance in Ulm in 1805). This happened so often that musters from 1806 and 1811 sometimes blankly omitted case of POWs, based on the assumption that nearly every soldier fell prisoner in the previous war. Therefore, for regiments who fought in Germany and Austerlitz in 1805, and in Bavaria and Deutsch-Wagram in 1809, one must also consult the monthly tables.

4. M/MIA (Missing in Action) – Recorded as Vor Feind vermisst or vermisst for short, this category denotes men who were missing when the battle ended. Anything could have happened to them. Some were dead (see rubric one), but others were taken prisoner, were lost, or deserted. The army recorded such missing men for the same reason as prisoners of war – to settle their backpay in future if necessary.

The total for each category of casualties is given at the bottom of the table for every war fought by the Habsburg army from 1792 to 1815. At the right hand side of the table are the grand totals for each category marked in red. At the end of every personal record are fields showing what happened to the soldier after he became a casualty. Wounded could recover or perish in hospital, while the prisoners and the missing could return. The same soldier could appear in the database more than once as he could be taken prisoner, be wounded or go missing several times. Only for those killed in action could the record be closed. For those who survived, the final fate was noted where known: discharge (including sub category), invaliding, desertion, or non-combat death. Men still in service when last mentioned in the documents are noted as ‘serves’. Whether complete or not, a detailed service record for each soldier as as I could reconstruct it from the sources is available in the database Jewish Soldiers of the Habsburg Army (1788-1820).

Names of all Belfortains who died for France during the First World War, classified by date of death. They are essentially soldiers who died in battle or died as a result of injuries or illnesses contracted at the front. Belfort numbered about 1450 deaths during the Great War. For more information, see the metadata on the Isogeo catalog.

A dataset to advance the study of life-cycle interactions of biomedical and socioeconomic factors in the aging process. The EI project has assembled a variety of large datasets covering the life histories of approximately 39,616 white male volunteers (drawn from a random sample of 331 companies) who served in the Union Army (UA), and of about 6,000 African-American veterans from 51 randomly selected United States Colored Troops companies (USCT). Their military records were linked to pension and medical records that detailed the soldiers������?? health status and socioeconomic and family characteristics. Each soldier was searched for in the US decennial census for the years in which they were most likely to be found alive (1850, 1860, 1880, 1900, 1910). In addition, a sample consisting of 70,000 men examined for service in the Union Army between September 1864 and April 1865 has been assembled and linked only to census records. These records will be useful for life-cycle comparisons of those accepted and rejected for service. Military Data: The military service and wartime medical histories of the UA and USCT men were collected from the Union Army and United States Colored Troops military service records, carded medical records, and other wartime documents. Pension Data: Wherever possible, the UA and USCT samples have been linked to pension records, including surgeon''''s certificates. About 70% of men in the Union Army sample have a pension. These records provide the bulk of the socioeconomic and demographic information on these men from the late 1800s through the early 1900s, including family structure and employment information. In addition, the surgeon''''s certificates provide rich medical histories, with an average of 5 examinations per linked recruit for the UA, and about 2.5 exams per USCT recruit. Census Data: Both early and late-age familial and socioeconomic information is collected from the manuscript schedules of the federal censuses of 1850, 1860, 1870 (incomplete), 1880, 1900, and 1910. Data Availability: All of the datasets (Military Union Army; linked Census; Surgeon''''s Certificates; Examination Records, and supporting ecological and environmental variables) are publicly available from ICPSR. In addition, copies on CD-ROM may be obtained from the CPE, which also maintains an interactive Internet Data Archive and Documentation Library, which can be accessed on the Project Website. * Dates of Study: 1850-1910 * Study Features: Longitudinal, Minority Oversamples * Sample Size: ** Union Army: 35,747 ** Colored Troops: 6,187 ** Examination Sample: 70,800 ICPSR Link: http://www.icpsr.umich.edu/icpsrweb/ICPSR/studies/06836

This study contains data on 779 dyadic fatal quarrels for the period 1809-1949. The study represents one of the earlier attempts at quantification of historical conflict behavior. A dyadic deadly quarrel is a situation involving a pair of opponents or belligerents which causes death to humans. Each quarrel is identified by its beginning date and magnitude. The magnitude of a quarrel is measured by the logarithm to the base 10 of the number of deaths. The range of magnitude of quarrels in this study is from 2.50 to 7.50, the latter representing the figure for nations involved in World War II. For each quarrel, the nominal variables include the type of quarrel, as well as political, cultural, and economic similarities and dissimilarities between the pair of combatants.