I replied to something similar a while back;
Paris falls in '14-'15? Britain calls a truce and like gentlemen the powers of Europe on both side re-carve the world. Millions live and the royals families of Europe still visit each other on the holidays. The Tsar (or at least the regime) falls and is replaced by a democratic state. Germany has a go at playing games with European trade and consumerism grips Europe leading to general prosperity (but with slightly less technological advance) And a man named Adolf plays soldiers and get's gunned down by police in a pathetic little Bavarian protest.
The Allies capture Berlin - This would never happen. Germany would have put it's hands up long before things got to that level (indeed in 1918 they still had some strategic advantage but were just bogged down). Had it been Russians who reached there in say 1916 then Germany calls a truce and like gentlemen the powers of Europe on both side re-carve the world. Millions live and the royals families of Europe still visit each other on the holidays. The Tsar (or at least the regime) reforms and becomes a democratic state. Russia has a go at playing games with Asian trade and consumerism grips Europe leading to general prosperity (but with slightly less technological advance) And a man named Adolf plays soldiers and get's gunned down by police in a pathetic little Bavarian protest.
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The Austrian-Hungarians, however, likely would have done quite differently. Italy would have experience major territorial losses in its Northeast, perhaps even losing Venice. Serbia would fall completely under Austrian rule, as would Montenegro and Albania. Romania would likely have been divided between Bulgaria and Austria. Significant ethnic strife, and cleansing" would likely have ensued.
The Ottomans would probably try to lay claim to Greece, but success wouldn't be assured, with some gains in the Caucuses. The Armenian genocide likely would have been even worse, and similar incidents would have occurred in all the lands the Ottomans nearly laid claim to.
I have a feeling the Ottomans would have walked away with nothing and collapsed anyway. Barring a few islands here and there, Greece was there to stay. The idea of surrendering the 'birthplace' of classical of European culture and thought (to which the Central Powers claimed to embrace) to the 'barbarous' and of course Muslim Ottomans would not be entertained. I have a feeling the Ottamans would have made a military move against Greece and seen Austrian forces intervene.
The Austrians would have room to territorially expand in the Balkans and in Venice. Moving beyond Galicia into the Ukraine and Poland was unlikely; Germany had no desire for manic expansion in Eastern Europe, but would create a half dozen buffer states (Poland, Livonia, Ukraine) between itself and Russia. Austria would get everything in the Balkans except Greece and Bulgaria. I agree Romana would have been vulnerable, but only to the extent that the Bulgarians got what was originally promised to them in the Treaty of San Stefano. Romania I can see being 'collapsed' into two client states, Moldova and Wallachia.
