World War I casualties The total number of military and civilian casualties in World War I was over 37 million . There were over 16 million deaths and 20 million wounded ranking it among the deadliest conflicts in human history . The total number of deaths includes about 10 million military personnel and about 7 million civilians . The Entente Powers ( also known as the Allies ) lost about 6 million soldiers while the Central Powers lost about 4 million . At least 2 million died from diseases and 6 million went missing , presumed dead . About two - thirds of military deaths in World War I were in battle , unlike the conflicts that took place in the 19th century when the majority of deaths were due to disease . Improvements in medicine as well as the increased lethality of military weaponry were both factors in this development . Nevertheless disease , including the Spanish flu , still caused about one third of total military deaths for all belligerents . Classification of casualty statistics . Estimates of casualty numbers for World War I vary to a great extent ; estimates of total deaths range from 9 million to over 15 million The figures listed here are from official secondary sources , whenever available . These sources are cited below . Military casualty statistics listed here include 6 . 8 million combat related deaths as well as 3 million military deaths caused by accidents , disease and deaths while prisoners of war . First World War civilian deaths are ' hazardous to estimate " according to Michael Clodfelter who maintains that “ The generally accepted figure of noncombatant deaths is 6 . 5 million ” The figures listed below include about 6 million excess civilian deaths due to war related malnutrition and disease that are often omitted from other compilations of World War I casualties . The war brought about malnutrition and disease caused by a disruption of trade resulting in shortages of food ; the mobilization for the war took away millions of men from the agricultural labor force cutting food production . The civilian deaths listed below also include the Armenian Genocide . Civilian deaths due to the Spanish flu have been excluded from these figures , whenever possible . Furthermore , the figures do not include deaths during the Turkish War of Independence and the Russian Civil War . Casualties by modern borders . The war involved multi - ethnic empires such as Great Britain , France , Germany , Russia , Austro - Hungary and Turkey . The diverse ethnic groups in these multi - ethnic empires were conscripted for military service . The casualties listed by modern borders are also included in the above table of figures for the countries that existed in 1914 . The following estimates of Austrian deaths , within contemporary borders , were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total dead 175 , 000 : including military losses 120 , 000 with the Austo - Hungarian forces and POW deaths in captivity of 30 , 000 . Civilian dead due to famine and disease were 25 , 000 Belgian Congo . The Belgian Congo was part of the Kingdom of Belgium during the war . Following estimates of casualties were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Czechoslovakia was part of Austro - Hungary during the war . The estimates of Czechoslovak deaths within 1991 borders were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total dead 185 , 000 : including military losses 110 , 000 with the Austro - Hungarian forces and POW deaths in captivity of 45 , 000 . Civilian dead due to famine and disease were 30 , 000 . The Czechoslovak Legions fought with the armies of the Allies during the war . Estonia was part of Russian Empire during the war and about 100 , 000 Estonians served in the Russian Army . Of them about 10 , 000 were killed . French colonies . The following estimates of French colonial military deaths , within contemporary borders , during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total military dead in French Army 81 , 000 . German colonies . The following estimates of German Colonial military deaths , within contemporary borders , during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total military dead 17 , 000 . The following estimates of Hungarian deaths , within contemporary borders , during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total dead 385 , 000 : including military losses 270 , 000 with the Austro - Hungarian forces and POW deaths in captivity of 70 , 000 . Civilian dead due to famine and disease were 45 , 000 Ireland was a part of the UK during World War I . Five sixths of the island left to form the Irish Free State , now the Republic of Ireland , in 1922 . A total of 206 , 000 Irishmen served in the British forces during the war . The number of Irish deaths in the British Army recorded by the registrar general was 27 , 405 . A significant number of these casualties were from what , in 1920 , became Northern Ireland . While 49 , 400 soldiers died serving in Irish Divisions ( the 10th , 16th and 36th ) Not all of the men serving in these divisions were natives of Ireland , for example 71 % of the casualties in the 16th Division were natives of Ireland . Poland was annexed by Germany , Austria - Hungary and Russia from 1795 – 1914 . By late 1915 Germany had complete control over modern - day Poland . A 2005 Polish study estimated 3 . 4 million Poles served in the Armed Forces of the occupying powers during World War I . Total deaths from 1914 – 18 , military and civilian , within the 1919 – 1939 borders , were estimated at 1 , 130 , 000 . The following estimates of Polish deaths , within contemporary ( post 1945 ) borders , during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total dead 640 , 000 : including military losses of 250 , 000 Poles conscripted into the following armies listed below . POW deaths in captivity of 20 , 000 . Civilian losses due to the war included 120 , 000 due to military operations and 250 , 000 caused by famine and disease . The ethnic Polish Blue Army served with the French Army . The ethnic Polish Legions fought as part of the Austro - Hungarian Army on the Eastern Front . The territory of Transylvania was part of Austria - Hungary during World War I . The following estimates of Romanian deaths , within contemporary borders , during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total dead 748 , 000 : including military losses 220 , 000 with the Romanian forces and 150 , 000 with the Austro - Hungarian forces and POW deaths in captivity of 48 , 000 . Civilian dead were as follows due to famine and disease 200 , 000 , killed in military operations 120 , 000 and 10 , 000 dead in Austrian prisons . British colonies . The following estimates of British Empire colonial military deaths , within contemporary borders , during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total military dead 35 , 700 . Britain recruited Indian , Chinese , native South African , Egyptian and other overseas labour to provide logistical support in the combat theatres . Included with British casualties in East Africa are the deaths of 44 , 911 recruited labourers . The CWGC reports that nearly 2 , 000 workers from the Chinese Labour Corps are buried with British war dead in France . Southern Rhodesia ( today Zimbabwe ) suffered over 700 military fatalities during the war . The following estimates are for Yugoslavia within 1991 borders . Slovenia , Croatia and Bosnia were part of Austria - Hungary during World War I . Serbia ( including Macedonia ) and Montenegro were independent nations . The Yugoslav historian Vladimir Dedijer put Serbian deaths in World War One at 369 , 815 military and 600 , 000 civilians . The following estimates of Yugoslav deaths , within 1991 borders , during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century . Total dead 996 , 000 : including military losses 260 , 000 with the Serbian forces , 80 , 000 with the Austro - Hungarian forces 13 , 000 with Montenegro forces and POW deaths in captivity of 93 , 000 . Civilian dead were as follows due to famine and disease 400 , 000 , killed in military operations 120 , 000 and 30 , 000 dead in Austrian prisons or executed . During WW1 , the Nepalese army was expanded and six new regiments , totaling more than 20 , 000 troops — all volunteers — were sent to India , most of them to the North - West Frontier Province , to release British and Indian troops for service overseas . Simultaneously , the Nepalese government agreed to maintain recruitment at a level that both would sustain the existing British Gurkha units and allow the establishment of additional ones . The battalions were increased to thirty - three with the addition of 55 , 000 new recruits , and Gurkha units were placed at the disposal of the British high command for service on all fronts . Many volunteers were assigned to noncombat units , such as the Army Bearer Corps and the labor battalions , but they also were in combat in France , Turkey , Palestine , and Mesopotamia . The Rana prime ministers urged Nepalese males to fight in the war . Of the more than 200 , 000 Nepalese who served in the British Army , there were some 20 , 000 Gurkha casualties included above with the British Indian Army . Notes on sources . The main sources used for military and civilian deaths ( unless stated otherwise in the footnotes below ) are as follows : The source of population data is : Footnotes . The conflict in East Africa caused enormous civilian casualties . The " Oxford History of World War One " notes that " In east and central Africa the harshness of the war resulted in acute shortages of food with famine in some areas , a weakening of populations , and epidemic diseases which killed hundreds of thousands of people and also cattle . " The following estimates of civilian deaths during World War I were made by a Russian journalist in a 2004 handbook of human losses in the 20th century : Kenya 30 , 000 ; Tanzania 100 , 000 ; Mozambique 50 , 000 ; Rwanda 15 , 000 ; Burundi 20 , 000 ; and the Belgian Congo 150 , 000 . The reported military casualties of the UK , France , Germany , Belgium , and Portugal include Africans who served with their armed forces . The details are noted in the footnotes of the various nations . Australia Included in total military deaths are 54 , 000 killed or missing in action and died of wounds The Commonwealth War Graves Commission Annual Report 2009 - 2010 is the source of the total 61 , 966 military dead . The ' Debt of Honour Register ' lists the 1 . 7 million men and women of the Commonwealth forces who died during the two world wars . The 1922 War Office report listed 59 , 330 Army war dead . Canada The total military deaths includes 53 , 000 killed or missing in action and died of wounds The Commonwealth War Graves Commission " Annual Report 2009 - 2010 " gives a total of 64 , 976 military dead . Includes 1 , 297 dead in the Royal Newfoundland Regiment . The Canadian Virtual War Memorial contains a registry of information about the graves and memorials of Canadians and Newfoundlanders who served valiantly and gave their lives for their country . The losses for Newfoundland are listed separately on this table because it was not part of Canada at that time , but are included in the CVWM registry . The 1922 War Office report listed 56 , 639 Army war dead Civilian deaths were due to the Halifax Explosion France The total includes 1 , 186 , 000 killed or missing in action and died of wounds The figure for total military dead of 1 , 397 , 800 is from a study published by the Carnegie Endowment for International Peace in 1931 The total includes 71 , 100 French Colonial Forces , 4 , 600 foreign nationals , and 28 , 600 war - related military deaths occurring from 11 / 11 / 18 to 6 / 1 / 1919 The UK War Office in 1922 estimated French losses as 1 , 385 , 300 dead and missing , including 58 , 000 colonial soldiers The U . S . War Department in 1924 estimated 1 , 357 , 800 killed and died The names of the soldiers who died for France during World War I are listed on - line by the French government . The French encyclopedia Quid reports that 30 - 40 , 000 foreign volunteers from about 40 nationalities served in the French army . At the end of the war 12 , 000 were in the Czechoslovak Legions and the ethnic Polish Blue Army . 5 , 000 Italians served in a " Legion " commanded by Colonel Garibaldi . There were also 1 , 000 Spaniards and 1 , 500 Swiss in French service . 200 American volunteers served with the French from 1914 – 16 , including the Lafayette Escadrille Luxembourg was occupied by Germany during the war . 3 , 700 Luxembourg citizens served in the French armed forces . 2 , 800 gave their lives in the war . They are commemorated at the Gëlle Fra in Luxembourg . The French Armenian Legion served as part of the French Armed forces during the war . French colonies , such as Algeria and Vietnam , also sent troops to fight for Imperial French . Almost 100 , 000 Vietnamese went to Europe to fight and serve on the French battlefront . Civilian deaths exceeded the prewar level by 500 , 000 . 300 , 000 were caused by military operations and food shortages , and 200 , 000 by the Spanish Flu Another estimate of the demographic loss of the civilian population in the France during the war put total excess deaths at 264 , 000 to 284 , 000 not including an additional 100 , 000 to 120 , 000 Spanish Flu deaths . Civilian dead include 1 , 509 merchant sailors and 3 , 357 killed in air attacks and long range artillery bombardments The French government did not provide an estimate of civilian deaths in the war zone , however tertiary source s have estimated civilian war dead at 40 , 000 . Greece Included in total are 11 , 000 killed or missing in action and died of wounds The Soviet demographer Boris Urlanis estimated total military dead of 26 , 000 including 15 , 000 deaths due to disease Jean Bujac in a campaign history of the Greek Army in World War I listed 8 , 365 combat related deaths and 3 , 255 missing Other estimates of Greek casualties are as follows : By UK War Office in 1922 : Killed / died wounds 5 , 000 ; prisoners and missing 1 , 000 . By US War Dept in 1924 : killed and died 5 , 000 Civilian deaths exceeded the prewar level by 150 , 000 , caused by food shortages and the Spanish Flu India ( British colony ) included present day India , Pakistan and Bangladesh . Included in total military deaths are 27 , 000 killed or missing in action and died of wounds . The Commonwealth War Graves Commission Annual Report 2009 - 2010 is the source of the total 74 , 187 military dead . The ' Debt of Honour Register ' lists the 1 . 7 million men and women of the Commonwealth forces who died during the two world wars . The 1922 War Office report listed 62 , 056 Indian Army war dead and 2 , 393 British serving in the Indian Army . Italy Included in total are 433 , 000 killed or missing in action and died of wounds The figure 651 , 000 military dead is from a 1925 Italian demographic study of war deaths based on official government data published by Yale Univ . Press . The details are as follows , Killed in action or died of wounds 378 , 000 ; died of disease 186 , 000 and an additional 87 , 000 deaths of invalids from 12 Nov . 1918 until 30 April 1920 due to war related injuries . Other estimates of Italian casualties were : by UK War Office in 1922 , Dead 460 , 000 and by the US War Dept in 1924 650 , 000 killed and died Civilian deaths exceeded the prewar level by 1 , 021 , 000 . 589 , 000 caused by food shortages and 432 , 000 by the Spanish Flu Another estimate of the demographic loss of the civilian population in the Italy during the war put total excess deaths at 324 , 000 not including an additional 300 , 000 Spanish Flu deaths . Civilian deaths due to military action were about 3 , 400 including 2 , 293 by attacks on shipping , 958 during air raids and 142 by sea bombardment . Another estimate of Portuguese casualties by the US War Dept in 1924 was 7 , 222 killed and died Civilian deaths exceeded the prewar level by 220 , 000 , 82 , 000 caused by food shortages and 138 , 000 by the Spanish Flu Civilian deaths in the 1914 borders exceeded the prewar level by 1 , 500 , 000 due to famine and disease and military operations . Civilian deaths in the post war borders , not including Poland , exceeded the prewar level by 1 , 070 , 000 ( 730 , 000 famine and disease and 340 , 000 military operations ) . The 1922 War Office report detailed the casualties of " soldiers who lost their lives " , " killed in action , died as prisoners , died of wounds and missing " from the Regular and Territorial Forces and Royal Naval Division : 702 , 410 from the UK , 507 from " other colonies " and 2 , 393 British serving in the Indian Empire Army . The figures include Royal Navy war dead of 32 , 287 The Merchant Navy war dead of 14 , 661 were listed separately Figures for total RAF are included in the totals of the War Office report Civilian deaths exceeded the prewar level by 292 , 000 . 109 , 000 due to food shortages and 183 , 577 by the Spanish Flu Another estimate of the demographic loss of the civilian population in the UK during the war put total excess deaths at 181 , 000 not including an additional 100 , 000 Spanish Flu deaths . The 1922 War Office report detailed the deaths of 1 , 260 civilians and 310 military personnel due to air and sea bombardment of the UK Losses at sea were 908 UK civilians and 63 fisherman killed by U - Boat attacks United States The official figures of military war deaths listed by the US Dept . of Defense for the period ending Dec . 31 , 1918 are 116 , 516 ; which includes 53 , 402 battle deaths and 63 , 114 non combat deaths . , The US Coast Guard lost an additional 192 dead . . " United States estimated civilian losses include 128 killed on the RMS " Lusitania " as well as 629 Merchant Marine personnel killed on merchant ships . A Russian journalist in a 2004 handbook of human losses in the 20th century estimated 120 , 000 civilian deaths due to military activity in Austro - Hungarian Galicia . The US War Dept in 1924 also listed 87 , 500 killed and died Civilian deaths exceeded the prewar level by 100 , 000 . due to food shortages . Norway and Sweden were both neutral in the war . They both lost ships and merchant sailors in trading through the war zones . Norway lost about 50 % of its merchant fleet , percentage - wise the highest loss of any nation ' s merchant fleet in World War I . 1 , 892 Norwegian merchant sailors died , mostly due to vessels torpedoed by German submarines . 877 Swedish merchant sailors died , mostly due to vessels torpedoed or sunk by mines .