"Map of the United States Territory of Oregon West of the Rocky Mountains Exhibiting the various Trading Depots or Forts occupied by the British Hudson Bay Company connected with the Western and Northwestern Fur Trade.", Abert/Hood
This map accompanied an important report introduced by Senator Lewis F. Linn of Missouri. It was intended to awaken public interest in the American occupation of Oregon Territory in the controversy with Great Britain, which also claimed the territory down to the Columbia River. Among the many interesting details are the locations of the various trading posts or forts connected with the northwestern fur trade, both American and British. The map was copied from John Arrowsmith's 1832 map of British North America and covers present day Oregon, Washington, Idaho, Montana, and Wyoming. The region west of the Rocky Mountains is named Mandan District where Lewis & Clark's route is shown. It also shows much of southwestern Canada. At bottom is the wording of an ultimatum given to the British by Henry Clay, Secretary of State, stating that the 49th parallel would be the boundary.