World War Nix
Nix are not yet defined vampire or werewolf type creatures who take over Earth, or try to. They reproduce by converting adult humans, and they survive by feeding on adult humans. (I'm trying to think of something like vampires or werewolves, without being vampires or werewolves.)
Since it's most logical an attack on the world would be focused on the strongest parts, the situation is that America, Europe, and Russia are taken over first. However, the Old Nix had to use mass conversion to accomplish their victory, and the New Nix are now in charge in all these places. In a few places around the world the Old Nix rule, in a few places humans have purged all Nix from the country, but in most of the world Free Humanity fights the United Nations, with a mix of Nix and humans on both sides.
Second American Civil War- Ongoing for several decades, static fronts, peace talks in DC, DC can still project power overseas,
There are four primary factions in the conflict, Federalists (Nix-dominated, Northeast, Great Lakes, Midwest, Northwest, New Orleans, Florida & Caribbean, Alaska & Hawaii), Restorationists (human-dominated, South, formerly Northwest, Great Lakes), Independents (human-dominated, Nevada, Utah, Colorado), and Constitutionalists (mixed societies, California, Arizona, New Mexico, Texas, Las Vegas, south of Oklahoma, Louisiana west of Mississippi). The region around the Mississippi and Ohio rivers, in most of Oklahoma and Kansas, and parts of the Rocky Mountains and Pacific Northwest, are dominated by feral Nix, who are a threat to even professional hunters.
Federalists want to bring America back under United States control, with the new Nix Amendments in place, granting Nix greater rights. Restorationists want to return the United States back to human control, with restrictions on Nix enshrined in the constitution. Independents are neutral, and tend to be human dominated. Constitutionalists have proposed deals that grant equal rights to both Nix and humans, and they have stable societies where these laws are already in place.
There are several new states in the United States. From Canada, New Brunswick, Nova Scotia, Prince Edward Island, and Newfoundland. In the Caribbean, there are Cuba, Puerto Rico, and Panama.
Canada is now several independent states, with some areas joining the United States. British Columbia is now the Free Republic, Yukon, Northwest, and Nunavut are now the Northern Republic, Alberta, Sasketchewan, and Manitoba are the MacKenzie Holding, Ontario is the Canadian Republic, Quebec is the Queendom of Quebec, and New Brunswick, Prince Edward Island, Nova Scotia, and Newfoundland are part of the USA. They are all members of the Nix dominated UN, but not all are Nix dominated internally.
The Nix were able to take over most of Europe quickly, but Free Humans and New Nix quickly broke their rule, and razed the institutions of the EU to the ground. In their place, the Western European Union, and several smaller trans-national unions, arose.
The WEU consists of England, France, the Low Countries, Germany, Austria, and North Italy.
The Union (of Scotland, Ireland, and Wales): Having been driven out of England, the royal family and human government of the UK established a government in Scotland. As the situation in Europe stabilized, they eventually formed a union with the Republic of Ireland. The population is seventeen million, nine million in Ireland, eight million in Scotland & Wales. The Republic has a population of eight million, the Kingdom a population of nine million. (this should be a different color, UN but human dominated, next iteration)