World War II
After World War I, having taken a break from the fighting for a couple of years, an all-out war broke out again in 1939. The two sides divided once again into vast forces and named themselves the Allied and the Axis.
During the short respite before the war, each country involved had decided to build new killing machines, making sure to take to the skies and the sea and creating more efficient land-based vehicles and automatic weapons their soldiers could carry.
And as if this wasn’t enough, a particular country decided to build a massive bomb. The Allies ultimately “won” the war. But unfortunately, about 85% of the death toll came from their side, with the Soviet Union and China seeing the most significant losses.
Most casualties also went outside the combat zone and can be attributed to war crimes.