20th-century Europe – What went Wrong? | See European Union.

In his book, ‘To hell and back’ published in 2015 (Allen Lane) Ian Kershaw paints a ‘broad picture of what went wrong in Europe in the 20th century [which] is built around four related points. First was the rise of ethnic nationalism, something that helped to doom the multinational empires of Austria-Hungary, Russia and the Ottomans. Next were demands for territorial revision, between France and Germany, in central and eastern Europe and all over the Balkans. Third was class conflict, as workers and a nascent socialist movement flexed their muscles against bosses and the traditional aristocratic ruling class. And fourth was the crisis of capitalism, which struck home in the early 1930s and contributed hugely to the rise of Nazism. 

Source: ‘A grim half century’, review of To Hell and Back by Ian Kershaw (2015, Allen Lane), The Economist November 14th 2015, p.74.