With a POD after 1870 have a war between the United States and Great Britain occur.
With a POD after 1870 have a war between the United States and Great Britain occur.
Some possibilities that have been discussed here in the past:
- A war over the Trent Affair. Most people feel the US would be curbstomped if we tried to fight Britain and the Confederacy at the same time.
- Escalation of the Pig War to an actual shooting conflict. This would probably be a very limited war, quickly resolved diplomatically, but political fallout could unleash a lot of butterflies.
- 54-40 or Fight isn't resolved diplomatically. This could go very badly for the US if the UK fully mobilizes its resources, especially if Mexico decides to force a decision over the Texas boundary dispute at the same time, but there's a good chance that Britain would decide that Oregon wasn't worth fighting a major war over.
All of which happened before 1870.
Maybe some controversy about the Russian sale of Alaska? London feels threatened by American expansion alongside the Pacific coast, so diplomatic conflict grows...
Considering there was still a great deal of anti-British sentiment in America up until the 1920s, it's not that much of a challenge. That border dispute already mentioned is one possibility. A fight over some Pacific islands (like Hawaii) is another potential spark. Crickey, even some unforeseen bone-headed diplomatic move could cause a war.
I toyed briefly with the idea of the Second Boer War becoming an international incident that led to the Great War, but I couldn't find the right POD. I was planning on having the US and UK being on opposing sides, but it's pretty implausible overall. I was think of having some ethical incident (y'know, with the prison camps) but there was no human rights indoctrination at that time.
As it turns out, there is some heavy oil in the Amacurao region that was part of the disputed area between Venezuela and British Guiana in 1894. IOTL, it didn't get discovered until a lot later, but ITTL, it gets discovered before Maracaibo oil does and John D. Rockefeller gets the rights to it. Only those rights are in jeopardy if the territory is part of British Guiana. That heats the dispute up to the point of war with the UK.