Within a year, miners in the eastern part of the vast Idaho Territory requested that a new territory be created for them. They were located on the eastern side of the Bitterroot Mountain Range and felt cut off from, and ignored, by the Idaho government located on the far side of the Bitterroots. Thus in 1864, the Montana Territory was created. Its eastern border was the old Idaho Territory with Dakota down to the 45th parallel. The southern border followed this line of latitude to 111 degrees west, then turning south for half a degree (44°30’), where it turned west again until it ran into the Continental Divide in the Bitterroots. From thence it ran along the crest of those mountains until it intersected the 116th degree line, which it then followed to the Canadian border.
- Wyoming’s western border was the 111th meridian
- Idaho’s border followed the Continental Divide until it intersected with the 111th degree line
- Montana’s border followed the 111th meridian to 44°30’, whence it turned west until that line intersected the continental divide.