I’ve always wondered how it was possible that after the First World War Austria was dismantled so thoroughly. From how I see it, while it could have been argued that Vienna was responsible for the war, it was Germany who kept the war going for four years. At the end of the war it clearly looked like the big bad boy of Europe and its potential of locking an entire continent in total war had been shown. So why was Germany treated, though still harshly, far better than Austria-Hungary at Versailles?
The obvious reason is of course the ethnic composition of the two empires. Germany was more or less homogeneous and overly german, while Austria-Hungary was a complete mess. But still it doesn’t seem enough. The Habsburg empire still had a rather strong identity, and if I can’t really see it keeping the slavic provinces, or even Hungary, Bohemia was still strongly connected to Vienna.
I guess what I’m trying to say is that Germany, the bigger threat, lost some provinces and had to pay and get humiliated, while Austria-Hungary was dismembered and thrown off the map. It doesn’t really seem fair, why not just break it in two/three parts? Why completely destroy an historical european power in a single war?
Two major factors by the end of World War ended the Habsburg monarchy, one being international and the other being domestic. The Versailles treaty had a strong element of geopolitical gamesmanship. While Austria-Hungary had been a second-tier great power in the lead up to World War I, it was still an important component in the continental balance of power. The Habsburg monarchy had played a significant role in acting as a check on German expansion as well as mitigating Russian influence in the Balkans. Somewhat similar to what the Allies did in the Middle East, breaking up the Habsburg lands into new nation states allowed them to have greater influence in the Balkans and East-Central Europe. These nations are particularly problematic when you look at an ethnic distribution map of the empire pre-war; you'll quickly see that none of the constituent hereditary crownlands of the dynasty had clean ethnic borders within the larger empire. And up until about 1917, no one anticipated that by the end of the war Austria-Hungary would be dismantled. Why this happened though is related to the domestic issues within the empire.
Contrary to what even many today still believe the empire was not a "prison house of nations" but throughout the nineteenth century underwent reforms. Historians of Austria-Hungary often theorize that if the empire had survived the war, its constituent "nations" would have been able to reach some sort of federalization or other structural change. Obviously this is a counterfactual, and in reality the imposition of German military rule late in World War I made many Habsburg subjects grow angry with the government, which at that point was more or less run as a German satellite. Hungary is a bit of a special case within the empire as with the 1867 compromise the Kingdom of Hungary became effectively its own autonomous nation-state that was linked to the rest of the country by the ruling dynasty. It was also the Hungarian policy of Magyarization (that is, forcing people to assimilate to Magyar-Hungarian culture) that made many of the national groups within Hungary disaffected. Again if you look at an ethnic distribution map you will see why this was a serious issue.
To conclude, what really impacted breakup of Austria-Hungary was imposition of German military rule late in World War I that inflamed existing tensions and motivated independence movements. Despite that the the breakup of the empire was not inevitable from the start of war, there was a serious lack of clear patriotism because Austria-Hungary was a unique state. Germany had developed clearer nation-state identity people could be loyal to despite the German Empire being made up of many traditional regional states and identities. The breakup of Austria-Hungary had serious long term geopolitical consequences that have gotten lost in popular discussions of World War II and into the Cold War and breakup of Yugoslavia.
Bohemia was still strongly connected to Vienna
I'm not sure what do you mean by "strongly connected". Czechs were loyal to Austria, although there were some important "buts".
Allow me to link this older thread where I explain what was the Czech sentiment/attitude to Austrian rule throughout the 19th century. Czech and Slovak politicians did start to pursue independence on the international diplomatic scene no sooner than at the beginning of the WWI. Before the war Czechs wanted to reform Austria-Hungary and gain better recognition and political representation. Only at the beginning of the WWI when they met diplomats in various countries they realized that such reforms were not viable; neither did the state of A-H government favour such changes, nor did the international diplomatic climate.
https://www.reddit.com/r/AskHistorians/comments/d6sel0/what_was_the_attitude_of_the_germans_to_the/