Idaho, as part of the Oregon Country, was claimed by both the United States and Great Britain until the United States gained undisputed jurisdiction in 1846. From 1843 to 1849 present-day Idaho was under the de facto jurisdiction of the Provisional Government of Oregon.
Between then and the creation of the Idaho Territory in 1863, parts of the present-day state were included in the Oregon, Washington, and Dakota Territories. The new territory included most of present-day Idaho, Montana, and Wyoming. The first organized communities, within the present borders of Idaho, were established in 1860.