I've said before that I don't think that it is at all an accident that Cooperstown is located at one of the most important waystations along this inland route. And, I would add now, Washington, D.C. (and Gettysburg) at others. That being said, there remains the question of how languages come to be aligned with geography.
This is a question that, in the first instance, inclines me to talk about a much smaller, walkable, professional geography. It is the case that some humanities departments at the University of British Columbia have their offices in one of the wings of the great spaghetti maze that is the Buchanan complex. So when the rain is pounding down on Vancouver, as has been known to happen, you might find yourself cutting through a long corridor of offices to get to your next class, rather than braving the courtyard outside. If you have a moment to linger, you can get some idea of what a department is about by reading the cartoons, funny clippings, and newspaper stories that people like to post on doors and notice boards. As an introduction to a field of study, it sure beats trying to read yourself into a textbook!
Now, one might ask why an expert in another field would want to do something like that? We have experts for a reason. No-one goes to an historian for an opinion about string theory, and the default presumption is that a physicist who wants to talk about history has gone a little dotty. Yet some of these departments bring together specialists from many fields. Take a trip down the hall through Classical Studies, though, and you'll see the point. The bulletin boards joke about archaeology, literature, and history, because Classical Studies contains (Classical) archaeologists, (classical) literature specialists, and (classical) historians. First come archaeological sites, then Greek literature, beginning perhaps 472BC by the absolutely most savagely skeptical, reductive approach I can imagine taking, then, sometime in the 430s, Herodotus of Halicarnassus writes his Histories under the patronage of the Alcmaeonidae. History is handed down from door to open door down the Classics Studies hall from archaeologist to literary scholar to historian, and the Classicists get to do all of us a favour by figuring out how history is going to relate to archaeology. Clearly there will be important lessons here for historians working on other areas at a similar transition point, such as the Eastenr Seaboad in the peri-Contact phase.
To follow the baton a little further, I'm going to take a walk through a campus that only exists anymore as a nostalgic memory, exiting out the north doors of the Buchanan complex to walk down back alleys and through a grove and across a field in the dripping rain under lowering skies* to the Vancouver School of Theology. Though even if we did that, we'd have to take the time machine of nostalgia back a long time further yet to the point where bible scholars intruded on the archaeologists's fields of toil to tell tales of pharaohs, Phoenicians, and Hittites.Not to mention Pythagoras studying hermetic secrets with the Jewish monks of Mount Carmel. Crazy? Perhaps. But mixed with uncomfortable facts.
So the Classicists sought allies amongst the ranks of the philologists, as I have discussed before. Allies with nigh unbeatable scientific talk swept away uncomfortable facts, bringing Greeks into Greece from the north at whatever time science currently leaves us (1200BC? 1500BC? 1900BC? 2500BC? 7000BC?) before hooking over the Aegean and colonising the Anatolian shore about 900BC or whatnot, just straight up exterminating the Orientals.
Which last? It seems invented --implausible, even. As though a story about Nineteenth (and Seventeenth) century colonialism is being resituated in the past so that its heuristic can have a longer lever arm with which to move the present. Stupid analogy? Let's be clear. It's not what the sources say. How do you get there with vehement certainty? In part, it's the jargon, but I prefer to visualise a sputtering academic, of a particularly embarrassing and embarrassed kind, babbling about Achaeans Indo-Europeans and Mediterranean Semitics and miscegenation.
On the one hand, I'm conjuring with a particularly repellent straw man here, and my only defence is that they existed in their myriads. On the other, I'm invoking a beguiling heuristic. If races are things given in themselves, separate and equal, then languages and cultures come in boxes that we can shuffle around the maps of our ancient mind's eye. Forget archaeology! There is no science for understanding the history that comes before history like historical linguistics! We've already applied this "science" to the Greeks, and there's no reason not to apply it to the Indians. I'll bet that you can't wait to find out where the Algonquins come from. (Hint.)
Way back in the world of credible scholarship, the classicists are getting better and better at founding history in archaeology. Why shouldn't we take the same approach to historical linguistics?
Actually, we should. But one more analogy here, this time with boxing. I've already linked to a brief discussion of Representative Seaborne Roddenberry's anti-miscegenation amendment to the United States Constitution, introduced into the House in January, 1913 in direct response to Jack Johnson's July 4th, 1910 victory over James Jeffries. At least for a historian of boxing, the mood in the United States in the wake of a black boxer's achievement of the heavyweight title seems a little ...frenzied. Could there be anything more petulant than trying to shut down professional boxing over this? (In favour of college football, just in case you thought that there was a public health case to be made) So Jess Willard's highly irregular victory over Johnson in April 1915 was taken hard by some. When this white, alleged "working cowboy" stepped into the ring for another 4th of July fight in Toledo, Ohio in 1919, he might have suspected that the man glaring at him from "Kid Blackie's" corner intended to set the boxing world to rights.
As with boxing, so with historical linguistics.