What I learned from looking through my options for Montana is that there are a truly disproportionate number of songs about Montana which explore the following theme: “I’m lonely because my baby left me, but at least Montana is beautiful.”
At the end of the day, I went with Nanci Griffith’s “Midnight in Missoula,” which (slightly) inverts this premise by placing her far away from home, wishing she could be back in Missoula with her loved one. It’s nowhere close to the best Nanci Griffith song–with production that feels very late 90s, and not in a good way–but even a mediocre song from her is still pretty nice.
For a more traditional iteration, try Hank Williams Jr.’s Montana Song, but stick with the live version. The studio take is airless and stale. You also wouldn’t go wrong with John Denver’s Wild Montana Skies which also feels quite dated sonically, but is a perfectly nice early 80s John Denver song. Plus, Emmylou Harris on guest vocals!
My favorite song associated with Montana is Box Elder by Pavement.