alternatehistory.com

In June, D-Day happens (one year later than OTL). At the same time, the Red Army manages to cross the Dnepr in the Ukraine. Truman fears that Stalin may swallow half of Eastern Europe, urges his scientists to work harder. Meanwhile, some German officers think that obviously everything is lost and think about killing Hitler.

But Truman decides otherwise. On the 22nd of July, the first nuke is dropped on the Northern German city of Oldenburg. For a while, nobody in Germany knows what really happened - not only half, but all of the city is destroyed, and there are barely any survivors (the city is smaller than Hiroshima). It takes some time until everyone in Germany understands what happened. Hitler seems not capable to understand that one city was completely eradicated. Even the conspirators against him are confused. They wait too long, and on July 26th the second bomb is dropped on the Austrian city of Graz. (There were many in America who protested, since the city was a cultural center, but it didn't help.)

Now the conspirators decide to act. Not by killing Hitler - there's not always the right opportunity, since Hitler has become more paranoid than ever - but by spreading mouth propaganda around in the Wehrmacht, discretely, what the officers think about ending the war. And other than Hitler, the generals agree that they don't want any more German cities not only bombed but eradicated - on every day, they get to hear more and more frightening stories from Oldenburg and Graz, although Hitler has strictly ordered not to spread such stories.

On the 9th of August, they start to act. Loyal Wehrmacht troops occupy radio stations in Berlin and other places, arrest Hitler and other nazi bigwigs, including nazi generals like Keitel and Jodl and strike against the SS. Otto Remer is among the killed.

Two weeks later, a provisional government is formed and starts to negotiate with the Western Allies - not with Stalin. In France, Italy and on the Balcans, the Wehrmacht retreats and gives the Allies control over the lands; in Russia, however, they continue to fight. Romania and Hungary let the Allies enter too, and the Slovakian government is toppled.

At the beginning, some men of the new German government don't seem to grasp the situation and seriously try to arrange that Germany may keep Austria, Sudetenland and parts of its conquests, but Churchill and Truman disagree. They demand that Germany is punished and aren't willing to make a compromise, although the Germans even offer to fight for the Allies against Soviet Russia. So the negotiations between Germany and the Western Allies start. The new government offers to leave the western countries and make a one-sided capitulation (only with the US and the Empire), which is declined too. The situation is so difficult because Truman and Churchill weren't really ready for the war in Europe ending before they know what to do with it. And Stalin is in the confusing situation that the Germans still have much territory of his country under their control, but stopped fighting the Western Allies - and were even able to transport troops to the East. And the new president Truman isn't that fond of Stalin - the conference in Moscow in February '45 didn't work out so well, and at Ankara in April the two of them didn't manage to find a compromise for the post-war Europe either. He even seems to have more sympathy for a collaboration against the Soviets. Stalin has to watch in anger how the Germans retreat from France, Italy and Bohemia. The Wehrmacht gives control over these countries to the Allies in an orderly fashion.

In October, what everyone would've considered unbelievable even three months ago becomes true: The Americans and Brits enter German territory, the local garrisons hand them over command, and hunt together with them for resisting SS men and other nazis. In the same month, Poland (in the borders of 1939!) and the Baltic states are occupied by the Western Allies. Stalin is almost mad, accuses Truman to be a traitor. But Truman points out the American strength and the bomb that has knocked out Germany and Japan (this part later), and tells Stalin to be content or get nothing at all. Stalin, grumbling, has to give in. Now Germany and the Soviet Union make an armistice, the Wehrmacht retreats (yes, Stalin can't even make prisoners), and the negotiations with all sides can begin.