Construction of the last Hudson Bay Trading Post within the present borders of the United States began here in 1846 and was completed in 1847 by Angus McDonald. Angus originally named the fort Connen after a river valley in his Scottish homeland, but later changed it to Connah for easier pronunciation by the Salish, Kootenai, Pend d'Oreille, and other Indians in the area. Fort Connah was built about 1/2 mile east of here and remained an important trading center for the Indians until the U.S. Government forced the British-owned company to abandon the post in 1871. At its height, Fort Connah consisted of only three buildings, and the store house is the only original structure that still survives. The Mission Valley was opened for settlement in 1910; before that it was almost entirely virgin prairie, unplowed, unfenced, and traveled by saddle horse. Many descendants of Angus McDonald still live in the Mission Valley.