Mitchell’s map of the American Northwest from 1863, the year that the territory of Idaho was established out of parts of the Oregon, Washington and Dakota Territories. It included most of what is today is Wyoming, Montana and Idaho. Just a year later, the eastern part of the territory was divided between the new territory of Montana and the remainder back to Dakota. This is the only version of Mitchell’s map to show the very large Idaho, though it does not show the entire territory, the eastern parts being beyond the scope of the map. Also of interest are the indications of the gold mines in Idaho (the reason it was settled and made into a territory), the “emigrant route” leading to Oregon and Washington, and the proposed route of the Northern Pacific Railroad.