A very ruff idea
Grey: The Confederate States of America
Blue: The United States of America
Green: New England
Yellow: The Californian Republic
Purple: The Nation of Deseret
Red: British/Canadian annexations
TL: Southern Hospitality
POD: Grant is killed in the American Mexican war
Basics: With the United Kingdom and France both recognise the Confederacy after a long string of Confederate victories. The US refuses to make peace so the British and French get involved with a blockade. New England and New York both seceded from the Union.
The US finally sues for peace.
New York joins New England.
British forces move into New England, London announces recognition.
Paris follows a week later.
Richmond the next day.
After the peace the US follows into economic collapse.
Things get worse for the USA.
And the CSA goes nuts with expansion. Cuba, Hispaniola, Puerto Rico fall to the CSA.
Other things happen, like Californian succession, do to economic issues and the CSA helping a Pro Confederate party come to power, and the CS threat of war if the US tries to stop them. They take two other states and two territories with them.
The Mormons take this chance, the CS backs them also moves in troops.
Britain buys Alaska, Montana, and Dakota(?) from the USA.
With no reason too, and no powers forcing them too, Confederate Slavery lasts up too 1912, when the TL starts.
Ideas? Thoughts?