allies war of 1812
NVA/VC vs US/allies
Its enemies were the Central Powers including Austria-Hungary, Germany and the Ottoman Empire. Its allies were the Entente Powers which included the US, the UK, Italy and France.
The US and the Allies won World War 2.
It all depends on the problem for why the war broke out. If a country tried to take over, then that countries allies would most likely be on that side and would be known as "enemies", while the other side would be known as allies. Some past allies would probably be allies again, like US, UK, France, Canada, etc.
The US joined the war on the side of the Allies on April 6, 1917.
Russia and the US went to enemies because when the war was over, they became superpowers and divided up Germany since Germany had a falling empire. They also made up their mind that Russia wanted Communism, and the US wanted a Democracy.
The opposite of allies (on your side) would be enemies. In World War I, the "Allies" were the Triple Entente and later the US and Italy, and were opposed by the Central Powers (Germany, Austria-Hungary, and the Ottoman Empire). In World War II, the major "Allied powers" were Britain, France, the USSR, and later the US, opposed by the Axis Powers (Germany, Italy, and Japan).
japan and Italy
allies
Allies.
Allies