US 231 was included in the inaugural routes of Nov. 1926, but at the time it ran only from Montgomery AL to Marianna FL. US 241 was not among the original routes*, but neither was it far behind: it was commissioned in Mar. 1930. This was mostly done to appease certain Alabama interests who wanted a US route designation to be applied to their State Highway 1.
*For the sake of clarity, there actually was a US 241 that was commissioned in 1926 to run between Nashville TN and Hopkinsville KY. However, it was never signposted as such in Tennessee, and possibly not in Kentucky either. AASHO officially canceled the US 241[i] designation in Jun. 1929, and its number was recycled less than a year later and applied to the route discussed on this page. To avoid confusion, this route is sometimes differentiated as US 241[ii].
A commercial state highway map from 1928 (by General Drafting) indicated that Alabama SH 1 ran through Huntsville, Guntersville, Gadsden, Anniston, Oxford, Talladega, Sylacauga, Alexander City, Opelika, and Phenix City. However, the official state highway maps from 1928 through 1930 illustrated a couple major differences. First, SH 1 was shown to extend farther south from Phenix City, through Eufaula, Abbeville, and Dothan. Secondly, these maps showed a different routing between Oxford and Opelika, passing through Roanoke and Lafayette (instead of Talladega, Sylacauga, and Alexander). Those official state highway maps are the ones that AASHO used as a source when defining the route of US 241 in 1930. But when US 241 was announced to the public, it caused an uproar from people along the original SH 1, who apparently were not previously aware that SH 1 had been rerouted along what I will call "the Roanoke cutoff" (since it reduced travel distance by about 27 miles compared to the routing through Sylacauga). They created such a stir that in Oct. 1930 Alabama sent the following telegram to AASHO, asking them to retract their original definition of US 241, and to instead describe the route as passing through Talladega, Sylacauga, Alexander, etc:
I find it a bit ironic that, by not allowing Alabama to signpost US 241 and SH 1 along the most direct highway, this so-called "Florida Short Route" organization was causing tourists to drive on a "long route": a highway that took them about 27 miles out of their way. That was exactly the sort of malpractice that the US route system was intended to abolish. But highways are a public expenditure, and as such it is difficult to keep politics out of it. Apparently AASHO did not push back, as they approved that change in Jan. 1931. So that was the route of US 241 and SH 1 that was illustrated on Alabama's official 1931 map (the first one that showed the new US 241 designation). It extended north from Huntsville, across the Tennessee line, through Fayetteville and Shelbyville to Murfreesboro, where it junctioned US 41 (which was the "parent route" implied by the number 241).
In 1935, at Florida's request, AASHO truncated US 231 about seven miles west of Marianna, and instead extended the route more southerly to a new terminus in Panama City.
In 1942 AASHO conditionally approved Tennessee's request to extend the US 241 designation north from Murfreesboro through Lebanon to its junction with US 31E near Westmoreland. The condition was that the highway had to be paved. It appears Tennessee completed that work not long after, but there is no evidence that they ever extended the US 241 designation north of Murfreesboro.
So, by the early 1950s, US 231 was running northward from Panama City through Dothan to Montgomery, while US 241 began at Dothan and went north to Murfreesboro. That was the timeframe during which the DOTs from several states began coordinating on a proposal for a new US highway. This route was envisioned to run all the way from the Chicago area to the Gulf Coast, and would pass through areas of Indiana, Kentucky, Tennessee, Alabama, and Florida that were mostly unserved by any north-south US route. The DOTs were aware that one option would have been to extend US 241 north from Murfreesboro to the Chicago area. However, they were opposed to that idea because US 241 ended in Dothan, whereas they were quite insistent that one of the key features of this new route was that it should extend all the way to the Florida Gulf Coast. That idea was present in this 1952 letter to AASHO from Kentucky:
Besides that stipulation, Kentucky and Tennessee had an additional dilemma to factor into the proposal. They wanted a US route designation applied to, not just one, but two different highways heading south from Owensboro KY. The western route passed through Russellville KY and Nashville TN, while the eastern route passed through Bowling Green KY and Lebanon TN. Each of these routes would rejoin in Fayetteville TN, but the mileage between Fayetteville and Owensboro was less via the western route.
In retrospect, it is easy to see an obvious solution that would have pleased all interests. US 231 could have been extended north from Montgomery via Huntsville to Fayetteville, then along the shorter (western) route through Nashville to Owensboro, then up through Indiana to the northern terminus. That would have created a Chicago-Gulf Coast route along the most direct corridor. Then US 241 could have been extended north from Murfreesboro, via Bowling Green to Owensboro. That would have addressed the eastern routing desired by Kentucky and Tennessee. In fact, that is exactly the arrangement that was proposed in the petitions sent to AASHO by the Kentucky and Tennessee DOTs in Mar. 1952:
However, AASHO did not approve the requests exactly as they had been proposed by the states. Why? There were a couple factors. For one thing, similar proposals for this Chicago-Gulf route had been sent to AASHO in years past, and they had been rejected primarily because AASHO was not convinced that the corridor actually merited a US route designation. And more generally, AASHO had been growing increasingly frustrated because states were continually proposing new US routes, but many of them were somewhat frivolous. If all of these routes were accepted into the system, then the US route shield was at risk of becoming rather meaningless.
So those were the concerns at top-of-mind for AASHO when they were asked to consider these proposals in 1952. For those reasons, in July of that year, AASHO responded to the states by offering a counterproposal. Their contingencies were as follows:
It is understandable why AASHO did not give the states exactly what they requested. Yet because they did not, AASHO would very soon have to revisit the routes that had been left out, and unfortunately some less-than-ideal outcomes would result.
Already by October, Alabama and Florida submitted petitions for a new US route along the corridor that had just been denied (i.e. Montgomery to the Gulf near Santa Rosa Beach). As a result, US route 331 was approved at AASHO's Dec. 1952 meeting.
In November, Kentucky and Tennessee applied for a US route between Owensboro and Springfield TN (where the new route would connect with US 41 heading into Nashville). Tennessee's application specifically noted that a new US designation was desired because, although Nashville was actually the destination for a significant percentage of traffic heading south from Owensboro, the freshly-extended US 231 bypassed Nashville. In Dec. 1952, AASHO deferred their decision on this route pending further study. During the next couple months, it appears that AASHO must have been contacted by some very irate people. No specific documentation to that effect was preserved in the AASHO archive, but this letter (sent by the Executive Secretary to the president of the Executive Committee on Route Numbering) leaves little room for misinterpretation:
I can only speculate, but I suspect that folks were upset because the new Chicago-Gulf highway did not follow the shortest route, and/or because it did not pass through Nashville. At any rate, AASHO had to revisit the proposal a third time in July 1953, and when they approved the new US 431, it was initially described as running between Owensboro and Fayetteville TN, where it junctioned US 231. Following is that paragraph from AASHO's meeting minutes:
At this point, let's pause and give a little more thought to the situation that existed as a result of that action. Between the south end of US 431 in Fayetteville and the north end of US 241 in Huntsville, there was a gap of only 30 miles. To anyone looking at this arrangement on a map, it would seem quite obvious that US 241 should have been extended north from Huntsville to Fayetteville, and then followed the western route through Nashville, ending in Owensboro. The US 431 designation was not needed. But even after it was unnecessarily established in 1953, it still would have been apparent that either US 241 should be extended north, subsuming US 431; or else US 431 should be extended south, subsuming US 241. Which of those options would have been best? Well, US 241 ran about 335 miles from Dothan to Huntsville, and it had already been established for 23 years. US 431, on the other hand, was a brand-new designation, and it was only about 205 miles in length. So to me, it would have been a no-brainer: extend the longer, more-established route (US 241) north, and eliminate the brand-new, shorter US 431 designation. If AASHO would have acted quickly enough, they could have made this change before US 431 had even been signposted.
But that is not what actually happened. In Aug. 1953 Alabama and Tennessee submitted a joint proposal to AASHO, requesting that US 431 be extended south to Dothan, replacing and eliminating US 241. AASHO summarized the petition as follows:
In a letter to the Route Numbering Executive Committee, the Executive Secretary used the phrase "your Committee", which was not typical, and which therefore seems to suggest that even he was not pleased with the previous decisions that had led up to this point:
Typically, the state DOTs were opposed to changing the number of a long-established US route, because this caused inconvenience to constituents who lived along that route, as well as confusion to drivers following maps that did not yet show the new number. But the following excerpt from Alabama's petition may hint at the reason why Alabama actually supported the elimination of US 241:
By that time it was obvious that US 241 should have been rerouted along the "Roanoke cutoff" mentioned previously. But Alabama was probably concerned that they would cause another storm of protest if they proposed that. They may have felt that it would involve less risk if they entirely eliminated US 241 and replaced it with a brand-new number that was defined to run along the shortest route between Huntsville and Dothan. Also, they tried to mitigate any fallout by concurrently requesting the extension of US 280 westward from Columbus GA. This extension covered the segment of former US 241 between Opelika and Sylacauga, leaving only the segment between Sylacauga and Oxford without a US route designation. AASHO approved both of those proposals at their Nov. 1953 meeting: