Alternate Histories: Not all are quite as obvious.
This is a long post. You've been warned.
I've tried to set The Burning Ages up as close to RL characters and with as much insight into the historical political situation as I could. In fact, I'm not ashamed to claim that I've probably come up with one of the most close-to-the-truth depictions of the situation featured in AH literature ever. What I wasn't aware of was the rat's tail of challenges this would present me with. Now, I do love a good challenge; this here is more to explain where this desire to stay true is leading me.
Ironically, killing Hitler or something to that end is usually the least of the problems writing AH brings with itself. You'll always find a dedicated group with admittedly varying influence willing o give you a helping hand in killing off the man with the funny moustache.
The less easy part is coming to the realization that you're not acting in a vacuum. That's were the tricky part starts. Because this is where your actions become less important, and the situation and historical actors move to the forefront. Say, you've killed Hitler in 1940. Fine, but what now? You've killed the most revered political leader of Germany on the height of his triumphs! Oh, sure, you do whatever you can to discredit his party and his close circle of leaders, but still: it's 1940, not 1945! So even if you end up fighting a civil war for Germany's soul and win it, you'll find yourself in a situation where you'll have to take a tougher stance for the simple reason you're not exactly sitting tightly in the saddle of leadership. Meaning you're ending up in a position in which your peace offers will amount to LESS than what Hitler repeatedly offered to Churchill (maybe not much less, but less nonetheless...less), i.e. virtually a return to the status quo ante. Why? Because you're risking to get hanged from street lanterns by people who aren't exactly keen to have to support you in the first place. "You wanna be better than the Nazis who did so well for us? Prove you can strike a better deal for Germany then. For the time being, you're on probation." Meaning the new government can't go for a quo ante deal out of pure self-preservation (though the deal they will offer isn't a bad one).
And then there's the problem of the Nazis. Yes, on the long run it's invaluable that you've fought them off yourselves. That way, Germany can walk out of this affair with its head held high. You beat them in battle, liberated the KZs, interned their leaders or shot them outright. But you won't have gotten all of them. Some will maintain an underground campaign against you, supported from some who've gone into exile. Also, some of the channels the Nazis used to try to initiate peace talks won't be available to you either (Dahlerus, for example). Furthermore, your de-nazification, if you try one at all, will be superficial, because, you know: you're still kinda in a war!
Now, leaving aside all the diplomatic shenanigans that'll happen between the parties of the Civil War and the German allies or German-leaning states in central and eastern Europe, what about Italy? How would a victorious anti-Nazi Germany deal with Italy? Logically, it'd try to rein in on its ambitions, but how likely is it that Mussolini would listen. And who would you talk to if he didn't? The King? Badoglio? Ciano? Would you want them to jump on the peace train, or would there be efforts to actually make them useful? Or both? And how would that impact the standing of the uptimers?
And if you think dealing with Antonescu in Romania or Mussolini in Italy would be awkward: what about the Japanese? Knowing about their horrendous conduct in Asia, this could very well lead to a break between parts of the uptimers and those downtimers who don't believe (maybe supported by uptimer knowledge) that a peace with the Allies is possible! And what then? Then you'd have two factions again, one trying to have nothing to do with the Japanese because frankly, they're the Nazis of the Far East, and another who'd try its damn best to foment a cooperation with the JE because it thinks it can use the Japanese to bind Allied forces and generally make their lives miserable!
The tricky thing about AH is that with the initial deed done the problems don't end. They, in fact, will just have begun. It's then that the morally clear-cut actions and impulses of the first act find themselves confronted with a situation where they might be no less right, but where „right" and „necessary and useful" are again different categories. Worse still if perceptive downtimers point that out: that war isn't a nice business where morally clear-cut decisions can be made, and that sometimes the devil you know is the better choice compared to the angel you don't know.
This also sets up the conflict between those who are morally right in their convictions and those who are objectively right in their analysis of the situation. Neither side is wrong. That's a compelling conflict.
Take, for example, the "Heim ins Reich" (return to Germany) policy of the Nazis. The morally correct judgment here would be that in many cases it amounted to nothing but ethnic cleansing (on part of the sending nation as well as on part of Germany which would displace other people to create space for the newcomers). Just as correct, however, is the analysis that the displacement of the eastern European German minorities (and other ethnics) contributed much to the peace in Europe after the war. We may all wish that people did not think in ethnic categories, but sadly, they do. Knowing that, what would a post-Nazi government do? Rationally, it'd follow the same policies as the Nazis did in that regard. It'd make deals with Soviets to get the Russo-Germans sent "home", too (also in the knowledge that such a massive transport of populations would clog up the Russian transportation network and slow down any potential troop upbuild of the Red Army).
In short, many decisions might have to be taken that may appear to have a bad taste, but which are more or less the logical or at least plausible result of the situation framed by historical facts and personalities.
Says my good friend James. Which brings us to the ugly issue of Winston Spencer Churchill. Churchill never seriously considered agreeing on some kind of peace with the German Reich IRL even when Hitler was in command of all of Europe and made the most sugar-sweet offers possible (it's important to know that Hitler admired the British Empire and saw it as the most important civilizing force in the world bar Germany). He wasn't alone in being unbent in his resolve to see the war through. While there were men as fanatic or even more so than Churchill himself - Lord Vansittaart, Arthur Harris, just to name some names - even those thought to be more moderate (Anthony Eden, for example) were convinced that Germany (and not specifically NAZI Germany) had to be beaten. There are ample quotes from the time to prove this. Peace-supporters like the Duke of Edinburgh or Lord Halifax soon found themselves sidelined or ignored, and GB left no means untouched in its efforts to mobilize against Germany.You are basically trying to put yourself in the mind of dozens of very complicated people with very complicated interactions and attampting to guess how it all plays out.
Then there's the two only consistent character traits of Winston Churchill: he was an Americanophile - and a Germanophobe. The latter only changed when he found himself in a bombed out German city after the war and people actually cheered him (it was also closely linked to the realization that "they had butchered the wrong pig"). There were a dozen or more peace initiatives started by Nazi Germany to come to an amicable agreement with Churchill's GB through different channels (Sweden, the Vatican and Switzerland the most famous ones), to return to a status quo ante. All were ignored (and I can't blame Churchill as much as I like there: the Nazis simply weren't trustworthy; that's a fact). And it stands to reason they would also have been ignored had the government not been one of Nazis, but of Prussian junkers, industrialists and conservative politicians. So much for real life. One can argue about why no peace was favored; in the end I assume it gets down to an obsolete view of foreign policy in which those men socialized by the idea of British Imperial dominance sought to play the old 'balance of power' game on the European continent. Only problem was that already by 1914 that game had been obsolete, and more so by the 1930s.
And now for how the death of Hitler can make a bad situation worse: The Luftwaffe offensive against GB will come to an early end; sure, the LW was the most Nazi-influenced branch of the Wehrmacht, so some squadrons would keep going at it on their own, with expected results. But on the whole, the air offensive would be stopped, with the LW ordered to a defensive posture. The uboat warfare against the British Isles also would be put on standby as to not poke the lion with a stick now that Germany itself is in inner turmoil (and a battlefield). And the reports from within Germany wouldn't exactly paint a rosy picture either; more one of the collapse of industrial production, uncertainty and inner strife (and open warfare). The new government would of course also use its spies (of whom it by then would know that they're in 99 out of 100 cases double agents) to tell the Brits one message: let's stops this, shall we? How about peace?
And what about the Brits? They've objectively won the BoB, their system has proven itself adequate, their enemy is in turmoil, their own production is unimpeded, the supplies are starting to flow in again, and they know that any idea of an invasion has been buried by the facts. Churchill's position will be cemented beyond any doubts. And he and others will demand that now would be the time to turn this thing around and go on the offensive: open the bomber war against Germany! Reinforce the Med and the Far East now that the Kriegsmarine is out of the picture, and deter the Japs and beat the living snot out of those Italians! Get the Balkan states on your side! Send more of your own and of the Commonwealth troops to Northern Africa and prepare for a push into Lybia and south-eastern Europe. With the threat to the British Isles pretty much ended, you can have close to a million Empire troops in Egypt; factor in the Greeks and the Yugoslavians, and you've got one hell of a broadsword to take to the Axis underbelly. And with a reinforced Force H, you can make the Mare Nostrum into the Mare Britannicum!
Not only would that be completely in line with Churchill's dispersionist thinking and his faible, nay, fetish with the Balkans: it would also be objectively correct! So, you're Winston Churchill and his war cabinet, and you've got an enemy in disarray and on his knees while your own side is soaring: would you agree on peace feelers from said enemy if you hadn't done so when he was much stronger? Or would you see a chance to beat down the Hun once and for all?
I'm not saying I like this scenario (though it's hard not to like it, since it totally plays with peoples expectations). What I do say, however, is that factoring in everything I know about the politics and the personalities involved, it's by an extremely huge margin the most likely outcome! It does make for some interesting writing opportunities, though.