To get a feel for what Montana was like when it became a state I recommend The War of the Copper Kings. It has all the corruption and shenanigans of that time period covered. And it's legacy of Superfund sites and severe distrust of politicians is a part of the state even today.

I am always disappointed when the future tech predicted in books takes decades longer to appear. On the opposite side is reading books written in the 90s and set in the near future. Nobody predicted the concepts of smartphones and bluetooth and internet very well.