In a world where the Cold War didn't stay so cold. Civilization had a fallout, with most cities and towns destroyed, the world is left to rebuild. The humans managed to preserve Technology, so rebuilding will not be too hard. Though the main thing that is different, The world is now divided into Totalitarian Governments, More moderate ones, anarchic states, and uninhabited wastelands.
So basically what happened is on April 21st, 1963, The Soviet Union bombed a United States Ship with 20 missiles. Unites States struck back, and what followed was a global war that ended up destroying almost every town in the world. In the end, the U.S.A surrendered and dissolved handing over the West Coast to the Soviets. Various other western nations were forced into Communism. in the aftermath of the war, Humanity was not bombed back to the stone age, but had to rebuild. After about a year after the war ended, Communism began to spread throughout the world. With this, Fascist, Monarchist, and all kinds of government forms began to seize power. The world became divided into factions. The Communists, The Monarchs, The Fascists, The Democracies/Republics, and The Free States. The Free states are a group of various countries that are uniting together to stop Totalitarianism.