A conventional reading of European history between 1917 and 1989 divides the era in two. In the first, catastrophic period, the collapse of the Austro-Hungarian, German, Ottoman and Russian empires yields an unstable political and economic order plagued by rival nationalisms, Bolshevism and democracies that turn into dictatorships, unleashing the second world war. In the later period, which has a more benign ending, the US and Soviet Union dominate one half of Europe each, leading to four decades of cold war tensions until the peoples of central and eastern Europe overthrow their communist systems.

As a broad overview, this reading of the era seems reasonable enough. But it has its limits. In particular, it risks imposing simplified interpretations on events, and underplaying less well-known trends, for the sake of a neat overall narrative. Two new books, Dominique Kirchner Reill’s The Fiume Crisis and Paul Betts’s Ruin and Renewal, are excellent examples of how modern historians are adding texture to our understanding of 20th-century Europe.

“Some stories are just too good not to tell,” writes Reill, a University of Miami scholar, as she opens her account of what happened in Fiume — today, the Croatian port-city of Rijeka — immediately after the first world war. The colourful story of Fiume has indeed been told before, but never with so many fresh and fascinating insights as Reill provides in her book.

Once a semi-autonomous city-state in the Habsburg empire, Fiume under its local Italian leaders clamoured after the war to be annexed to Italy. The Americans, British and French would not allow it. In September 1919 the poet-adventurer Gabriele D’Annunzio, a wartime celebrity defined by narcissism, unapologetic debauchery and aggressive nationalism, marched into Fiume with a band of paramilitary supporters.

D’Annunzio postured with a bizarre mixture of theatrical politics and mystical authoritarianism before Italy’s armed forces booted him out in December 1920 and compelled Fiume to accept its internationally determined status as a sovereign city-state. There matters stood until Benito Mussolini, who had seized power in Rome in 1922, annexed Fiume to Italy two years later.

For decades, historians have viewed the Fiume crisis as a prelude to fascism in Italy and as emblematic of the violent hyper-nationalism and scorn for democracy that afflicted Europe between the world wars. Reill shows that these interpretations, though containing much truth, gloss over crucial details of the Fiume episode.

By focusing on currency disorder, school curricula, ethnic surnames, adaptations of the legal system and citizenship rights, she explains that the objective of Fiume’s civic leaders in 1918-1920 was not merely to join Italy, but to preserve as much as possible of the self-government which the city had enjoyed under the Habsburgs. For example, Fiume adopted the Italian penal code but kept the Habsburg-era right to divorce, outlawed in Italy.

“Nationalist politics held sway, but were still subsidiary to the rights of localdom,” Reill says. Local rights were a lost cause under Mussolini but Reill’s book reminds us that extreme nationalism did not sweep aside the Habsburg empire’s legacies in central Europe as quickly and comprehensively as is sometimes assumed.

Betts, a historian at St Antony’s College, University of Oxford, is interested in how civilisation became a principle “summoned to help redress Europe’s crisis of identity” after 1945. This is often told as a story of the growth of liberal democracy in western Europe, the EU’s creation and the anti-communist struggles of the east. However, Betts concentrates on less familiar aspects of the period in a way that makes his book original and stimulating.

To begin with, he describes the enormous humanitarian relief efforts launched in 1945 by intergovernmental agencies and religious charities to assist tens of millions of displaced people across the continent. Staffed mainly by people from Britain, Canada, France and the US, these efforts showed “how quickly the crisis of civilisation moved from confusion and despair to co-ordinated international action to confront the damage of war and to care for its victims”.

Betts illustrates how British views of Germany moved from contempt to compassion as masses of ethnic German expellees arrived from the east, their suffering documented in “photographs of gruesome destitution and misery” appearing in the British press. Victor Gollancz, the London Jewish publisher, argued that humane treatment of Germans was a supreme moral test for Britons if they wished to live up to their self-image as a civilised people. In 1953 Gollancz was awarded the Order of Merit, West Germany’s highest state honour.

Another unusual angle from which Betts views the postwar years is that of popular religious sentiment. Pilgrimages, reported miracles and the cult of the Virgin Mary enjoyed a boom, as after earlier European wars. Meanwhile, the 1949 show trial of Cardinal Jozsef Mindszenty in Stalinist Hungary turned into a cause célèbre of the cold war, pitting what conservative politicians such as West Germany’s Konrad Adenauer and Italy’s Alcide De Gasperi saw as Christian, western civilisation against godless communism.

European civilisation appeared in a less attractive light as Belgium, Britain, France, the Netherlands and Portugal fought what were ultimately hopeless battles to hold on to their colonies in Africa and Asia. In Europe itself, however, Betts draws attention to the resurgence of “manners manuals” in both west and east — guidebooks to civility in daily life after the war’s inhumanity.

There is much else to ponder in Betts’s book, including his warning that, for many on the European right, “the call of civilisation now means the defence of white Christian identity and the closure of borders to immigrants”. Clearly, the alarmist idea that Europe is a “civilisation in crisis” does not convince everyone. But it has been “reactivated . . . in ways not seen since the early cold war”, concludes Betts.

The Fiume Crisis: Life in the Wake of the Habsburg Empire, by Dominique Kirchner Reill, Belknap Press, RRP£28.95/$35, 312 pages

Ruin and Renewal: Civilizing Europe After World War II, by Paul Betts, Profile Books, RRP£25/Basic Books RRP$35, 536 pages

Tony Barber is the FT’s Europe commentator

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