A long time ago, two countries called Canada and the United States had a disagreement about where their border should be in a place called Alaska. Both countries wanted the land to be theirs because it was very big and had a lot of resources like oil and minerals.
To solve this disagreement, both countries asked another country called Great Britain to help them. Great Britain was a powerful country that had control over the land at the time.
After a lot of debating and looking at maps, Great Britain decided that Canada should have some of the land, and the United States should have the rest. This decision was called the Alaska Boundary Dispute.
Both Canada and the United States were a little upset about the outcome, but they agreed to respect the decision and marked the new border with signs and markers. Today, Alaska is a state in the United States, and the dispute is no longer a problem.