Challenge: The American West, a Land of Many Republics

The challenge here is to take the American west, northwest, and southwest, and balkanize it as much as possible. There are many nations which attempted to create themselves, such as the Republic of California, Republic of Texas, Deseret, Cascadia, and even Burr stealing Louisiana, and so on, so there is some logic to this. The goal is to have as many of those coexisting in the same reality as possible.
 
I think without the Mexican War and US expansion in the region you'd see independent Texas and California in the long run. If you can somehow cause Manifest Destiny to never happen.

Possibly comparable to balkanization of Central America OT, but the trouble is the region is not populous enough to easily support multiple independent states.

I would like to see some Native American polity in the region survive, but it ain't likely.
 
Make someone screw up and deprive California of statehood before the Civil War and you have a country that wants to go independent there.
 
Make someone screw up and deprive California of statehood before the Civil War and you have a country that wants to go independent there.

You could also have the government refuse to give California its massive size and make it a requirement that it be broken up, or that it surrender its claim to the Sierra boundary, which would PO California.
 
You need an early POD within US expansion, but I don't think it is implausible.

Lets say the US goes to war against Britain in 1807 over the Chesapeake affair; unlike 1812 Britain is not distracted by the Peninsular War, and things go badly-ish for the US; the peace treaty is not too harsh but the US is forced to accept a more Southernly border than the 49th parallel; and butterflying the 1818 treaty away Britain has full claim on the Oregon-Country.

After this give the US a more Whig-ish mindset and it could, instead of expanding, try to set up friendly republics as trade looks west.

First goes Texas, as in OTL.

In the 1870s Californian immigrants secede from Mexico, but are later unable to keep the Mormons and Navajo in their borders, so you get two little ones. Mexicans/Pueblo Indians secede from Texas and make the Southern Rocky Republic.

At some point Oregon/New Caledonia gets fed up with Britain and establishes a republic. (And earlier on if Britain took Michigan/Wisconsin from the US they choose to go their own way as well as they are pretty much stuck between to rival neighbors, call it the Great Lakes Republic or just Michigan).
 
Failed American revolution and varioues Boer-style republics set up inland. The British authorities don't really think it's worth their while to subjugate them.
 
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