Diabolical Oregon Trail

Place names in the Americas are a fascinating blend of words derived from indigenous usage ("Multnomah") mixed with names borrowed from other places ("Salem"), simple descriptors like "Springfield" or "Rocky Mount," family names, and more abstract appellations. I was curious to discover if, in this latter category, places in the United States with names incorporating words like "Devil" or "Hell" might share any characteristics; my suspicion was that "bad" toponyms would be attached more frequently to places of topographic or climatic extremes. A simple map of such place names in the contiguous US seems to reveal the general outline of areas of high relief, like the Appalachians, Ozarks, Rockies, Cascades, Sierra Nevada, etc.

I decided to use the Oregon Trail as my study area, reasoning that places within a 20-mile buffer around the Trail with "diabolical" toponyms had a good chance of having been named by emigrants passing west during the mid-1800s. At least a quarter million pioneers traversed the Oregon Trail in its heyday, and they named the things and places they encountered along the way, or, if the place already had a name or two, courtesy of trappers or voyageurs, the emigrants settled on a popular option and reified the toponym for future maps and narratives. After expanding my criteria to include place names connoting death, starvation, calamity, blood, massacre, and the state of being lost, and pruning away duplicate names and things like post offices or campgrounds named for nearby features, I ended up with 145 relevant locations in my study area. I then set out to discover what sorts of physiographic and spatial factors might have influenced the way these places were distributed along the Oregon Trail.

After grabbing a digital elevation model and looking at the map it was pretty obvious that elevation alone didn't have much to do with how these places were named, since malignant toponyms were far more abundant after the trail moved over the South Pass and began its long descent to the Columbia basin. So I used the model to create rasters for slope and for a metric I came across called the Terrain Ruggedness Index (TRI).

Calculating TRI is a way to quantify terrain complexity, and for the purposes of modeling challenges to movement is a more comprehensive measure than mere slope. It's useful for planning military operations, search & rescue, etc., and has some utility in predicting biodiversity. My hunch was that diabolical or calamitous place names would be more frequently attached to more "challenging" terrain, but to judge from the scatter plot below it seems that the most important factor in naming places like this along the Oregon Trail was the distance of the feature from the start of the emigrants' journey at Independence, Missouri.

Perhaps segments of the Oregon Trail further from Independence had more nearby malignant place names because they were more deadly. An estimated 4% of travelers died on the way to Oregon during the Trail's heyday, so certainly there was a higher cumulative number of deaths as the parties moved west. But what about mortality rates on different parts of the Trail?

In the summer of 1852, emigrant Cecilia Adams noted 401 fresh graves along the Trail, and guessed there were perhaps five times more. Deadlier segments of the Trail ended up with fewer bad place names; Unruh (1979) estimates that half of all Trail deaths occurred east of the Rockies.

As the Oregon Trail descended from its highest point at Hellhole in what is now eastern Idaho, it plunged into the vast lava fields of the Snake River plain. Igneous geology would dominate the landscape from here to Oregon City. Perhaps the occasional stink of sulfur from hot springs, or the dramatic views, or the practical difficulties of traveling over and through weathered basalt made diabolical names more likely after this point.

58% of key toponyms describe places in igneous geological units, which make up only 27% of the study area. Although some igneous units have a low mean terrain ruggedness index, average TRI still tends to increase as the geology becomes increasingly basaltic and andesitic moving west along the Trail.

One limitation of this study is the lack of temporal data concerning when these places were actually named. My assumption has been that most toponyms of interest in the study area were put into use over the course of the Oregon Trail overland emigration, or if named earlier, had persisted and were reified by the settlers as they moved west. A more thorough investigation into when these places were named would help focus additional research on historical and cultural features of Trail toponomy.

The Terrain Ruggedness Index is illuminating but using it to gauge challenges to travel along the Trail is limited by its lack of human scale granularity, since differences in micro-elevation might indicate barriers to movement than can't be identified when using a 30-meter scale raster to compute the index. Finer-grained elevation data would likely be more useful in trying to assess the practical and perceived ruggedness of some parts of the Trail, and would no doubt help explain why the path sometimes seems to veer through highly rugged terrain along the border of a lava plain that, according to the index here, is relatively smooth.

Finally, there is an obvious correlation between the frequency of these sorts of place names and distance from the beginning of the Trail in Independence. Likewise, beginning at the Snake River plain, landscapes become increasingly volcanic in nature as the Trail goes on. At the same time, although death rates were lower once the emigrants had reached the Rockies, the cumulative number of dead travelers, along with lost livestock, broken equipment, malnutrition, harrowing river crossings, and camp drama, must have had an aggregate effect on the psychology of the emigrants. By the time they reached the lava fields of Idaho they were probably grumpy and pessimistic and had stopped trying to be polite when naming things.

It's also possible that the greater frequency of these sorts of names as the Trail goes west is due to the fact that there are simply more things to name. The prairies of Nebraska are punctuated with a few landmarks but are for the most part unremarkable from a traveler's point of view. Regardless, besides the practical matter that travel through the Pacific Northwest was increasingly challenging for these already-exhausted emigrants, the visual impact of dramatically weathered volcanic landscapes in Idaho and Oregon likely helped inspire them to give out more "bad" names than they had when involved in milder portions of the Trail east of the Rockies, where if ever there had once been lava, its traces had long since been erased.

Rudimentary statistical analysis confirms that diabolical place names along the Oregon Trail are significantly more frequently attached to landscapes characterized by igneous geology, which in this context occur only along the western portion of the emigrants’ route. Igneous landscapes also tend to be much more “rugged” on average than non-igneous locales; necessarily, designated places of interest are significantly more rugged than would be anticipated from a sample of places randomly distributed along the length of the Trail. Of the different types of place names, those incorporating the terms “devil” and “hell” have the greatest affinity with highly rugged terrain, regardless the underlying geology.