There were approximately 10 million people killed in the first World War. The largest number of these casualties were French, Russian, German, Austria-Hungarian, English and Italian. The Americans lost a large number of people as well, estimated at more than 100,000, but some of the European countries lost more than 1 million soldiers.
A large portion of the soldiers killed lost their lives to bombs and grenades. It is estimated that nearly 60 percent of the deaths wee from these sort of attacks. The Russians and Germans, two of the first countries to enter the war, had the highest losses. Russia lost around 1.7 million people and the Germans lost just shy of 2 million people.