Ok, I will be quick and post a rudimentary TL higly open to suggestion.
So, as per the title we have partly more succesful spring offensives by the German Empire during Spring 1918...partly succesful means the germans do not reach Paris, but they smash the BEF and seriously threaten french position to the point of general panic. Now the germans are out of steam, but the french do not know it.
A cease-fire is agreed by both parties and negotiations begin. Both parties hang in the balance: french back is broken, but the germans are in a desperate situation, concerning both supplies and manpower, incapable of fully exploting their victory and haunted by the specter of fresh british and amrrican troops arriving later that year (but the french do not totally know that).
While negotiations go on both parties keep their forces mobilized.
In the end a provisional agreement is drafted, wich advocates for basically white peace on the western front, with Germany aknowledgeing the loss of it's colonies and the western allies recognizing the treaty of Brest-Litovsk.
The proposal draws much opposition from both sides.
Now in Germany when the text of the agreeiment is rendered public riots erupt in the streets, the mood being "4 years of bloody war for nothing" (here I am assuming that France being the archenemy to average germans, then victory in the east are seem as a minor affaire, by the great public). This resentment combines with the greater one from the increasing shortage of basic goods, due to the ongoing British blockade in startling what will basically be a stronger 1918 revolution in germany, made even worser by the fact that the army is still deployed in the West (no large freikorps at hand this time).
Now the germans need to close the war quickly, and the french have meanwhile realized that, to such an extent where some in their staff pushes for a renewed offensive, now that the germans are on their last legs; this, btw, will prove unfeasible, as in the mean time, french army has been partially demobilized and is riddened with defections. Also, as a plus french public, as well as german, has by now, it's own distorted opinion of the war situation.
In the end a new resolution is drafted where Germany, namely as compensation for western recognization of the treaty of Brest-Litovsk, will hand Alsace-Lorraine back to France.
The proposition draws widespread outrage in Germany, but german establishment knows time works against them, and that they need to bring the army back home and quell the riots, so they agree.
The french on their side would like to ask for more, but they are nearing collpase as well.
In the end a treaty is signed with the germans also agreeing a "substantial reduction" in their navy so ad to sopra se the british (wich are quite disgruntled at not achieving a true victory because of french wellness)
TTL treaty of versailles will be Sd follows:
-on the eastern front, everything as per Brest -Litovsk (so major german victory, period)
-on the western front, A-L goes to France, Eupen and Malmedy to Belgium, along with token reparations, plus, the germans will reduce their naval strenght to 1/3 their current levels (no limits on type or tonnage of ships, btw)
german colonies will be shared as per OTL.
No war reparations of any kind (except those destined to Belgium).
Ironically, this will all come too late.
Ok, more to follow tomorrow; bear in mind, I have a detailed plan; your questions will be adressed.
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