Sir Compton McKenzie got the inspiration for his book from a real life event.
This is a film I have seen many times and I have read the book. It was lovely to get the DVD and see the extras. It had to be retitled for the American anti-alcohol lobby and the ending had to be altered to show that the Islanders gained no benefit from stealing all that Whisky.
I seem to recall that the times I have watched it before, the ending was different, or perhaps I am confusing it with the book.
The upshot is that the Islanders did not suffer in the slightest from secreting "the water of life" and everyone lived happily ever after.
As a matter of interest, Whisky was rationed and scarce in the UK during the war, yet boatloads were exported to the USA.
WATCH THE FILM - AND - READ THE BOOK!!!!
You will not regret it.