World War II was a global conflict that involved world powers, organized into two apposing military alliances, the Allies which included The United States of America, Soviet Russia and The United Kingdom, which was known as "The Big Three". Opposing the Allies were the Axis and the countries under this faction were Germany, Japan and Italy. The war involved the mobilization of 100 million military personnal, making it the most widespread war in human history. The participants exhausted all their economic, industrial, and scientific capabilities at the service of the war effort, erasing the distinction between civilian and military resources. During the 6 years of terror, over 70 million people perished, majority of the deaths were civilians, making it the most costly war in human history.