WW2 was a large-scale military conflict that included large parts of the world and pitted the Entente powers (France, Great Britain, Russia until 1917, and others) against the Central powers (Germany, Austria-Hungary and others). Many soldiers died in inconclusive trench battles that characterized WW1, losing thousands of troops for less than a mile of advance typically. The result of the war was inconclusive, with the main participants each weakening themselves to try to prevent another world war.