<P> The total number of military and civilian casualties in World War I was more than 41 million: there were over 18 million deaths and 23 million wounded, ranking it among the deadliest conflicts in human history . </P> <P> The total number of deaths includes from 9 to 11 million military personnel and about 5 to 6 million civilians . The Triple Entente (also known as the Allies) lost about 6 million military personnel while the Central Powers lost about 4 million . At least 2 million died from diseases and 6 million went missing, presumed dead . This article lists the casualties of the belligerent powers based on official published sources . 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 . Nevertheless, disease, including the 1918 flu pandemic and deaths while held as prisoners of war, still caused about one third of total military deaths for all belligerents . </P>

What were the casualties of world war 1