I haven't given this the thought it truly deserves so I'm going to brainstorm a bit here.
Christian crusades which obliterate Muslims to the point of extinction.
The South wins the Civil War.
Germany wins The Great War.
Rome never falls. (if Rome never falls is there even a Germany? It gets hard to think all this out)
The Egyptians destroy fleeing Jews before they reach the Red Sea.
The goal would be to change things early enough that would prevent other things from happening that also need changed. A butterfly effect.
Maybe even save one, if that is within the rules, change the future past.
The South wins the Civil War.
There never was a war of north vs south. There was only judeo-communist-Democrats-bankers vs Republicans.
Would have been better for everyone to have two separate countries. The west probably would have broken off too to make it present US into three separate countries.
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