Wars displace people. The ‘exodus’ – the flight south in May and June 1940 of a good part of the population of northern France, including Paris – was remarkable. But it was not unique. Less than five years later there would be a comparable exodus in eastern Europe, as Germans – many belonging to families settled for generations in the Baltic States, Poland, and the territories that were once part of the Habsburg empire – fled before the conquering Red Army. When the Hitler war ended there were millions of unfortunates officially labelled DPs – Displaced Persons  (refugees, as we would now say) – to be resettled. Those old enough to remember newsreels of the Korean War will recall pictures of South Korean peasants and the citizens of Seoul in flight from the Communist armies of North Korea and China. This should be remembered. The French exodus in 1940 was not exceptional.

Hanna Diamond, a Senior Lecturer in French History at the University of Bath, tells the story vividly and even-handedly. Panic unquestionably set in. It was all the greater because for seven months after war was declared in September 1939, nothing happened in the West. This was what we called the