I often write that the Red River of the South occupies the space in "the Old Southwest;" my blog's tagline is actually "where the South meets the West." But not everyone understands what I mean by that: when I've mentioned that the Caddos were one of the Southwest's oldest cultures, for example, I was scoffed at. After all, this scoffer must have been to New Mexico and Arizona, the "actual Southwest," where villages have been continuously occupied for thousands of years. How could the Caddos be one of the Southwest's oldest civilizations, then?
The answer is based on historical and political geography.
Direction, as used historicall, is relative to where a person stands. When the United States came into being, politicians and surveyors used cardinal designations in relation to Washington D.C. aka Virginia/ Maryland/ Delaware (okay, first it was Philadelphia). This is why today's states of Michigan, Ohio, Indiana, Illinois, and Wisconsin were designated "the Northwest" and any land reaching beyond the Cumberland Gap (Virginia, Tennessee, Kentucky) to the Mississippi River was "the West." Georgia and the Carolinas were "the South," a geographic and political designation synonymous with "slaver power."
The Old Southwest
South of Georgia was Florida, a Spanish possession. Florida was not just confined to the current-day peninsula and panhandle.... the Spanish claimed today's Mississippi and Alabama (and for a few decades, Louisiana), too. Then, when the United States purchased Louisiana Territory in 1803, the geographic designations relative to the U.S. seat of government changed. "The West" was any place beyond the Mississippi River, and a new designation, the "Southwest," became the land west of the Mississippi River but south of the 36th parallel, which Henry Clay designated in 1820 as the country's new political and geographical division between Free and Slave states. This parallel was the country's actual dividing line between slave and free states, not the "Mason Dixon line," which was in reality a localized boundary dispute left over from the colonial era.
The state of Louisiana and the portion of the Missouri Territory that would become Arkansas and Oklahoma were below the 36th parallel and thus, could legally be slaver states. And this is the "old Southwest" that I refer to when I mean the Red River Valley is in the Southwest. Because most of the history of the geography formed after the Louisiana Purchase has been linked to slavery, it makes sense to designate the states as "south," and because most of their history has been tied to Manifest Destiny, it makes sense to designate the area "west," too.
The Current Southwest
In 1845, the U.S. gained Texas, and in 1848, it claimed the Mexican Cession, which includes today's New Mexico, Arizona, Utah, Nevada, and parts of Oklahoma, Colorado, and Wyoming. When looking at a map today, these states definitely are "southwest" of Washington D.C., just like the states of Oregon, Montana, Idaho, and Washington are definitely "northwest" of Washington D.C. This is how the country derived the current view of the Southwest and Northwest, both ONLY cardinal directions that do not explain the historical and political geography.
The Treaty of Hidalgo of 1848 between Mexico and the United States prohibited the US to make the Mexican cession, which existed below the 36th parallel, into slave territories. In 1850, the U.S. Congress passed an act that allowed the ceded territories to elect to allow slavery or not as they became states, and then extended this provision to Kansas and Nebraska (of the former Louisiana Territory and well above the 36th parallel)... and this was the precursor to the American Civil War.
The Red River Valley
American politics played an outsized role in the geographic designation of the Red River Valley, and politics may be the reason why the ancient people of the Red River -- the Caddos-- have not been given as much recognition regarding the actual cultural input of the "Old Southwest."
In the modern Southwest's history, the Spanish did horrendous things to the native people, known as Pueblos from the Spanish word for villagers: they forbade their religion, built missions on top of their cities, enslaved a large portion of the population, and destroyed their foods and life ways, all in order to "Christianize" (the word back then was to "civilize") them. But today's New Mexico, Arizona, Texas, and Utah were very far from Mexico City, the center of the New Spain, and land-hungry "manifest destiny" was not part of the Hispanic ethos. Coupled with the Pueblo uprisings in 1680, some of the cultures had a chance of remaining visible when the Spanish forged new colonial ways.
In the Old Southwest, the native people did not experience an uprising. The Caddos, if they were able, aligned themselves with the French. Those who lived under Spanish domain found themselves being shunted from one place to another. Then, when the Spanish/Mexican government allowed white Americans and American slavery to enter the Old Southwest, the Caddos lost whatever hold they had on their homelands. Eventually, treaties with Americans led them to becoming stateless and nomadic. Their once mighty culture diminished within the first three decades of the American Louisiana Purchase, and evidence of their occupation of the Red River Valley has been looted and/or erased.
The "Old Southwest," which is dominated by the Red River, is a political rather than a cultural designation.
