We find some more evidence as to the circumstances under which Grant reportedly made this remark if we read the paragraph that sets the stage for the quote:
The editor of the Randolph Citizen recalls some interesting reminiscences of the great Reticent. He had a tongue at one time, it would seem:
In the summer of 1861 General Grant, then Colonel of the Twenty-first Illinois Regiment of Infantry, was stationed at Mexico, on the North Missouri Railroad, and had command of the post. He remained several months, mingling freely with the people, regardless of the peculiar shade of anyone’s political opinions; and as the distinguished Colonel had then no thought of aspiring to the Presidency or a dictatorship, no occasion existed for the reticence to which latterly he owes the greater part of his popularity. Ulysses the Silent was then Ulysses the Garrulous, and embraced every fair opportunity which came in his way to express his sentiments and opinions in regard to political affairs. One of these declarations we distinctly remember. In a public conversation in Ringo’s banking-house, a sterling Union man put this question to him: “What do you honestly think was the real object of this war on the part of the Federal Government?”
This is useful information. Colonel Grant and the 21st Illinois were located at Mexico, Missouri, from July 23, 1861, until August 7, 1861 (the following day he assumed command of a military district at Ironton, Missouri). So now we have a time span for the encounter … and we know that Grant was indeed in Mexico, Missouri.
What of the Randolph Citizen? Well, we know it existed, being printed in Huntsville, Missouri. Files of the paper are scattered. Huntsville is nearly 50 miles northwest of Mexico, Missouri. We know from this rate book that the paper leaned Democratic as of 1870, and it’s reasonable to think that was the case in 1868; however, additional research suggests that in 1861 it was a free soil paper that went out of business, to be replaced in 1864 by a pro-Democratic paper. We can see, however, that in 1868 the source of the story was not disinterested politically: he was supplying his fellow Democrats with information.
And what of Ringo’s banking house? Well, A. R. Ringo founded a private bank in Mexico in 1861. So there’s a banking house.
So, we have verified the location of the banking house, confirming that it was indeed in Mexico, Missouri, and further confirmed the existence of the Randolph Citizen and discovered that the editor in 1868 was a Democrat. More things seem to be falling into place … until next time.
Crossroads 
In “Triumph over Adversity” one gets the impression that with “several troublesome regiments at Mexico,” Grant should hardly have had time to socialize. He was still organizing his staff. as well. He did have some interaction with the locals and it was by his account positive. He also assessed the local political atmoshpere, and came away convinced that they were sure the war was about abolition.
If I had to guess, I’d say Grant may have made the first half of that statement but I find it absolutely out of character to offer up a reserved option to take his sword and serve the Confederacy.
Maybe.
Actually, he claimed that he had ample time to socialize with the locals, who were all deluded secessionists that didn’t believe a word he had to say, and were convinced that the United States was waging a war of abolition. So while the heat of his rhetoric may have been magnified by the lense of time, the meat of what he was reported to have said to the locals certainly rings true, even if it was said to win their hearts and minds.
After all, he was busily waging a war against guerillas in a hostile countryside. Any measure of cooperation he could coax from the locals would surely prove invaluable.
And how do we know that the rhetoric of what was said is being exaggerated? Because in 1861 we learn from Grant that there was not a Union man among them. The local papers were very pro-secessionist and people were leaning towards the Confederacy, if not in overt support, at least in the mistaken belief that the federal army was being driven back on all fronts with great loss and the town had better side with the ultimate winner. The idea that there was a “sterling Union man” openly posing a loaded question surrounded by Confederate sympathizers in an area full of Confederate guerillas seems a bit far-fetched.
Not to mention the context of the question. Why would a sterling Union man be grilling the local commander about the ultimate strategic goal of the U.S. army? Clearly the question is being posed by someone who is at least on the fence.
“Actually, he claimed that he had ample time to socialize with the locals, who were all deluded secessionists that didn’t believe a word he had to say, and were convinced that the United States was waging a war of abolition”
I think I said as much.
I don’t take that from that section of the book, nor do I take that as being in Grant’s character to do. To me, it simply is not Grant. Remember I am referring to him vowing to switch sides if he discovers that the war was over abolition. I think Grant was smart enough to perceive that the outcome of the war would result in both a victory for the Union and restoration of the seceded states, AND the end of slavery in some form, be it immediate emancipation or gradual.
Grant may have been inept at farming and being a merchant, but he was no dummy, nor was he a fool. He was teaching himself new tactics that were put into play since the Mexican War and his earlier departure from the Army. He was also smart enough to allow Washburne to back him. So he was politically savvy, though he played his cards close to the vest. Why?
I think he wanted to be on the winning side and he knew which one that was. When it came to his own career he played it that way, when he was mixing socially in unfriendly circles he had to take the “company line,” and that was: “restore the Union.”
I don’t see him expressing himself against abolition as that would surely have shown up in some newspaper somewhere soon after he said it, and gotten him in deep yogurt with his superiors.
He would have been seen as making disloyal statements.
I may be wrong on this, but that is my take. I just don’t see Grant saying anything like that. Too much of a downside to it.
It doesn’t read like the “voice” in the Memoirs.