How could this be? The history of Europe’s past half-century is usually depicted as step after step toward a common future. But maybe, to understand where we are now, the story should start earlier — not with the coalescing of France and Germany in the 1960s but with the model of Europe in the decade before the calamity of 1914.

In important ways, the Europe of 1913 was more cosmopolitan and European than the Europe of today. Ideas and nationalities mingled and converged in a hotbed of creativity. That year saw the height of Futurism, the beginnings of abstraction in Picasso and Braque, the debut of Stravinsky’s “Rite of Spring,” the publication of “Swann’s Way” by Proust. Collaborations to uncover science’s deepest secrets jumped borders easily. The architecture of imperial Austria and republican France found imitators in smaller gems of cities throughout Central and Southern Europe; they were called Little Vienna or Little Paris.