Montana’s frontier days were stuffed with gold, greed and political corruption — and all three played a part in drawing the state’s western boundary with Idaho. A listener wants to know how that squiggly line came to be. How did Montana get its shape? Learn more in this episode of the Big Why.
This episode was originally published on June 21, 2023
Austin Amestoy: Welcome to the Big Why, a series from Montana Public Radio where we find out what we can discover together. I'm your host, Austin Amestoy. This is a show about listener-powered reporting. We'll answer questions, large or small, about anything under the Big Sky. By Montanans, for Montana, this is the Big Why.
This week, we're tackling another foundational question about Montana — one that "frames" the whole concept, if you will. It comes to us from Pat Ryan of Butte.
Pat Ryan: "How exactly did Montana get its borders?"
Austin Amestoy: Ryan says he's always been interested in Montana history, but recently found himself wondering why our western boundary with Idaho is so wonky. It follows the continental divide north until it reaches the southern tip of the Bitterroot Mountains, then follows that range toward Canada. Ryan wondered why the border stops following the divide.
Pat Ryan "But, I've never been able to find anything that says one way or the other, so I thought I'd ask you guys."
Austin Amestoy: I've got Montana Public Radio producer Nick Mott here with me to retrace our state steps. Hey, Nick.
Nick Mott: Hey, Austin. This is such a good question. I've never actually thought about the story behind the state's shape.
Austin Amestoy: You know, I hadn't either. But, it turns out it's a tale loaded with gold, greed and corrupt, cutthroat politics — and, the border story isn't over either.
Rep. Denley Loge: "What happens if somebody takes 50 acres from you? From anybody?"
Nick Mott: Ooh, I'm intrigued.
Austin Amestoy: Well, let's set the mood for a trip back in time, then.
"Montana Territory" (1956): "This is Montana. She's beautiful and rugged."
Austin Amestoy: The United States bought most of the land that would become Montana from the French as part of the 1803 Louisiana Purchase. Historian Shane Doyle, a member of the Crow Tribe, told me American politicians didn't really consider Montana valuable at the time. To them, it was rugged, empty and inhospitable during long winters.
Shane Doyle: "I think the government and many people at the time thought, you know, 'Give it to the Indians. Let the Indians have it if they want it. I mean, there's nothing there for us.'"
Austin Amestoy: On the other hand, the Plains Indians called it home for thousands of years prior, when what we know today as Montana was carved off from Idaho Territory in 1864, Doyle said the state was divided entirely into seven huge reservations.
Nick Mott: Wow. The whole state?
Austin Amestoy: That's right.
Nick Mott: Well, even then, that had to be a smaller area than the tribes had originally called home historically, right?
Austin Amestoy: That's right, it was. And those reservations would only contract from there as a gold rush to areas near Virginia City picked up during the 1860s. Settlers suddenly saw value in this once "barren" place. Doyle says they began to arrive in droves in search of wealth, and a series of wars and treaties with native tribes eventually shrank reservation boundaries to where they are today.
Nick Mott: There's that gold you mentioned earlier. I had no idea it played such a big role in how Montana's borders were drawn.
Austin Amestoy: It really did, especially when it came to that unusual western boundary. But, it turns out there's some intrigue in straight lines, too. To answer Pat Ryan's question. I turned to the local library and a little book called "How the States Got Their Shapes," by Mark Stein.
Nick Mott: Well, let's start with those straight lines, then. How did Montana's northern border with Canada form?
Austin Amestoy: Yeah, according to Stein's book, that line came about when the U.S. and England, which controlled Canada at the time, agreed to use the 49th North line of latitude to divide the two nations from Minnesota to the Pacific coast.
Nick Mott: Got it. That's simple enough. And what about the eastern border with the Dakotas?
Austin Amestoy: Interestingly, that line was decided for similar reasons to the southern border. It turns out there's a mathematical reason behind our eastern and southern borders.
Nick Mott: Wait — states were divided using math?
Austin Amestoy: In a way, yes. Congress at the time was really bent on this idea of drawing states of somewhat equal size. So the eastern and southern borders were drawn as a way of keeping Montana about the same width and height of some of the territories nearby.
Nick Mott: Wow, that's so fascinating. But, there's no chance math can explain the weirdness in that western border.
Austin Amestoy: That's definitely right. And, I knew there had to be a good story behind that line. So, I reached out to Mark Stein for an interview — he wrote that book on state shapes. Stein told me Montana's boundary with Idaho was really the work of a single man: Sidney Edgerton.
Nick Mott: Alright, so, who is this guy? I haven't heard of Sidney Edgerton.
Austin Amestoy: Maybe most famously, he was Montana's first governor. But, before that, he was a federal judge appointed to serve in Idaho Territory by President Lincoln in the 1860s. Like many politicians in the frontier days, Edgerton was power-hungry. Stein told me it didn't take long for Edgerton to find his "in."
Mark Stein: "Edgerton, at some point in this story, acquired interest in gold mines."
Austin Amestoy: Eventually, Congress determined Idaho Territory was just too big to govern and began the process of dividing it up. The territory's leadership at the time wanted the boundary with Montana to continue straight up the continental divide. But Edgerton knew the value of those mountains and the gold they could contain, and he wanted to take a bite out of Idaho's claim. He pocketed some gold from the Bannock area and went to Washington to lobby House Territorial Committee Chairman James Ashley and President Lincoln, both of whom he was good friends with.
Nick Mott: So, what ended up happening?
Austin Amestoy: Well, if you look at a map today, the border does diverge from the continental divide when it hits the Bitterroots. So, Edgerton definitely "won." And, I'll let Stein tell the rest.
Mark Stein: "How did he win? No one knows for sure. But, I'll read you something from The New York Times from April of 1869, just a phrase about James Ashley — that there was 'abundant evidence of political corruption.' So, I kind of think that when [Edgerton] showed them the gold, he may not have remembered to take it back."
Nick Mott: Wow, that's just crazy. Who knew one guy could have so much influence drawing a border? And I guess that also answers that question about the state's wonky western boundary Pat Ryan was curious about.
Austin Amestoy: Yeah, the whole story really blew me away. And, as I was reporting, I dug up quite a few surprising anecdotes about Montana's boundaries. But, there was one more I just had to share. Nick, have you ever heard of Montana's modern-day border dispute?
Nick Mott: I have not, Austin — tell me more.
Austin Amestoy: Yeah, I hadn't either. But, one Montana state representative has been following the story since day one.
Austin Amestoy: "Representative, where are we?"
Rep. Denley Loge: "We're at the top to Lookout Pass, Idaho-Montana border, and we're in the parking lot of the ski area."
Austin Amestoy: Rep. Denley Loge is a Republican lawmaker from St. Regis, about a half-hour drive from the border. He's familiar with the pass and the boundary because he helped build and maintain the highway that connects Mineral County in Montana to Shoshone County in Idaho. Loge says the border historically ran along the Bitterroot Mountains' drainage. But, at some point after the highway was built in the 70s, he learned that Shoshone County had drawn maps claiming the line was a few hundred feet to the south into Montana, where the drainage had shifted after the highway was complete.
Nick Mott: Wait, so can a border just move like that?
Austin Amestoy: Well, not really, no. A border can only move with an act of Congress, even if the thing that was used to draw it, like a river or a drainage, in this case, moves for some reason. Loge had some pretty convincing evidence, too.
Denley Loge: "You see where there's a difference. And, it's very obvious — the difference where Idaho builds their road and where Montana starts their road.
Austin Amestoy: Where Loge pointed, there was a clear, straight line in the pavement right where the drainage used to be.
Nick Mott: So, what's the big deal, though? What's the value of that disputed few hundred feet of land?
Austin Amestoy: Well, Loge says Mineral County is missing out on tax money from the Forest Service and from the ski resort. But more broadly, he told me the border is a matter of principle.
Denley Loge: "Just because they draw a map, how should they get 50 acres of Montana and everybody just ignore it and let it go away?"
Austin Amestoy: I couldn't reach Shoshone County for comment, but Loge says he just got funding approved during this year's state legislative session for a federal survey of the border. He hopes Montana will be able to present the results to Idaho to get the boundary sorted out once and for all.
Nick Mott: Austin, thanks so much for the border breakdown.
Austin Amestoy: It's my pleasure, Nick. Now we want to know what makes you curious about Montana. You can submit your own questions online at bigwhy.org. Find us wherever you listen to podcasts, and help others find the show by sharing it and leaving us a review.
