Alaska is the Alayska SSR. The Soviets gained control of Alaska in World War 4's conventional stage, and after years of abuse by oil barons, corporations using it to dump toxic waste, and the US army constantly passing through and causing trouble, the Soviets were actually greeted as liberators by the Alaskans. They full-heartedly embraced Communism, but after World War 4 went hot, the Moscow government took Communism in a totally different direction. The Alayskans seceded, but they still remained allied to Moscow.
Northern Canada is the People's Republic of Nunavut, an Inuit-dominated republic which joined the Soviets for similar reasons to the Alayskans, but was never formally incorporated.
The Laurentine People's Republic was established in the post-apocalyptic landscape of Quebec by Quebecois radicals.
The capitalist government in Western Siberia is the Far Eastern Republic, formed by Mongols who broke off of the USSR after World War 4. They're led by an American deserter who claims to be the living re-incarnation of von Ungern-Sternberg. Using a mixture of cavalry and Japanese vehicles and arms, they've proved an effective thorn in the side of the Soviets, and are competing in a great-game of their own with the Japanese for influence with the Chinese Warlords.
The Atom-Kings are American mutineers. During World War 4, it was the Americans who first ordered the use of a non-tactical nuke, because Russian troops were winning and had made it so far through Canada. Most of the silo commanders refused to initiate Armageddon when the US could just hang up its hat and admit defeat. After the war, these silos got hit extremely hard by bombs, and the radiation has isolated them from the outside world. They formed fiefs, centered around their missiles; some were scrapped, others rigged into a nuclear reactor, but most are used to threaten one another and hold the rest of the world hostage. They demand large tributes from the US and the Soviets every year to keep themselves functioning. Since ICBMs are banned/ lost, if either side were to gain control of the Lands of the Atom-Kings, they could win the war.
