The year is 2450. And all is in war.
The first Nation is the Russinese. Russia and China had fused themselves for more power, and ended up taking over all other Asian nations.
The second nation is the Spanars Nation, they were formed not by war, but by advancement. They were busy working on more technology while the other nations grew and fought. They were the first to make it to Mars, but at a cost. Their home nation was conquered by the European March few years after they had set up themselves on Mars.
The third Nation is the Americans. They were made by the fuse of several North American nations. These nation went on to conquer other nations in North and South America.
The last Nation is the Eurafrican Confederation. They were made also by conquest. Several European countries worked together to slowly conquer the continent, and eventually, became powerful to the point of their foes surrendering. At the same time Africa had diverged into two main nations, both becoming weak from their large war. When the strong European foes came, both were forced to surrender.
By 2380 the four nations had turned Australia into a nuclear waste with their war.
By 2410 Antarctica had been stripped to the rock, the ice covering the land barely two inches thick.
The nations are using time travel to return to 2015, to conquer the barren lands before they were turned to ash.