The ""History Of Oregon Territory"" is a book written by Thomas Jefferson Farnham in 1844. It provides a detailed account of the exploration and settlement of the Oregon Territory, which at the time included present-day Oregon, Washington, Idaho, and parts of Montana and Wyoming. The book covers the early expeditions of Lewis and Clark, as well as the later efforts of fur traders and missionaries to establish a presence in the region. Farnham also describes the conflicts between the Native American tribes and the white settlers, as well as the political tensions between the United States and Great Britain over control of the territory.