He is talking about the relationship between the British Monarchy and the Colonies. And he calls it a “union”. That is so he can make his bad analogies comparing the American Revolutionary War to the American Civil War. It just means he is getting tired and is relapsing. When he mentions his magic kingdom, called the “British Union” then it is really time for him to take his nighttime meds.
I think he harps on the transcontinental railroad, so maybe we’ll hear about Union Pacific next.