Passport to Pimlico (1949)

I think this ranks amongst the best of the post-war British comedies. The residents of an heavily bombed-out part of London are deliberating what to do with some waste ground when an unexploded bomb goes off on the site leading to the discovery of a fantastic medieval treasure. Amongst this treasure is a document identified by an on-form Margaret Rutherford as the ditzy professor, that states that these residents are not Londoners at all - but Burgundians. Dazzled by pride and the value of their hoard, they declare a sort of UDI and the story unfolds from there. This film typifies the "blitz" spirit that many Londoners experienced and the sense of community and determination not to yield to any form of oppression is writ large in the clever, witty and Oscar-nominated script. A great ensemble cast keeps this whole, quite short, feature highly enjoyable.