This question relies on a lot of handwavium, but I am asking out of general interest more than anything;
Revolution X occurs in Britain near the beginning of the Great War, causing the home islands to fracture into England, Ireland and Scotland - what happens to Britain's colonies? I assume the dominions will just go their separate ways, but what about the Royal Navy? How does this affect the war? Would each nation sue for peace separately? Would the new nations be recognised?
I know this is ASB, but I don't like posting things there since this section generates far more discussion and I'm looking for plausible effects rather than plausible causes.