As long-time (and very patient) readers of this blog will know, I am fascinated by the historical evidence for what I term air panics. Most obviously this includes phantom airship and mystery aeroplane panics, but also rearmament panics, Zeppelin base panics, red balloon panics... anything and everything which provides evidence for what the British people thought and felt about the danger of aviation.
Perhaps the best-known example of an air panic is the exodus from London in September 1938 at the peak of the Sudeten crisis. Supposedly some 150,000 middle or upper class people fled west in anticipation of a German air attack.1 Such a large movement of people represents impressive evidence for the reality of a fear of a knock-out blow from the air. But I've never looked into this in any detail, and nor, as far as I know, has anyone else. So we don't know much about what actually happened during the 1938 exodus, or why.
The 1938 exodus was not, of course, unique. (People had trekked out to the countryside to avoid air raids in the First World War.) It wasn't the only one in the British Empire. (There was one in Australia.) In fact, it wasn't even the biggest. As I was surprised to learn from reading Srinath Raghavan's India's War, numerous spontaneous evacuations due to the fear of air raids took place in India in 1941 and 1942.2 Admittedly this was during wartime, but some of these panics took place before Japan entered the war, and others from places that were never even threatened by air attack.