Section 3: Changes in Land Claims
It is likely that other adventurers and fur traders journeyed to North Dakota from time to time after the visits by La Vérendrye and his sons, but there are no records of any such visits for about half a century (50 years). The next recorded trip to the area was made by David Thompson over 50 years later.
Between 1754 and 1763, Great Britain and France were at war. The British called this war the "French and Indian War" because the Indians helped the French. Spain helped France win this war. In 1762, France secretly gave Louisiana to Spain in payment for its support.
Great Britain defeated France. These two nations signed the Treaty of 1763. This treaty gave Great Britain possession of all the land drained by rivers that flow into Hudson Bay. This included the Red River of the North and the Mouse (Souris) River and their tributaries. Therefore, eastern and northern North Dakota became part of Great Britain’s empire.
Spain still owned Louisiana including the part of North Dakota drained by the Missouri River and its tributaries. North Dakota was not part of the United States at that time.