The outdoor scenes were shot in Lambeth, a mile away from Pimlico. A set was built on a large World War II bombsite just south of Lambeth at the junction of Hercules Road. This site is now the location for municipal flats build in the 1960s. However, the buildings on the junction of Hercules Road and Lambeth Road can still be recognized from the film, as can the railway bridge going over Lambeth Road, particularly from the scenes where food is thrown over the blockade.
At the start of the film a radio announcement mentions Latin music performed by "Les Norman and his Bethnal Green Bambinos". This is an in-joke referring to Ealing producer Leslie Norman. Bethnal Green was an unattractive area in the East End of London.
When the traders invade Pimlico, a comment is made about it becoming "a spiv's paradise". A spiv is/was a minor criminal who dealt in stolen or black-market goods of questionable authenticity. Spivs were often well-dressed and were noted for offering goods at bargain prices, though the goods were generally not what they seemed or had been obtained illegally. The term was particularly used for black-market dealers during the Second World War and in the post-war period.
Inspired the likes of The Mouse That Roared (1959) and its sequel The Mouse on the Moon (1963) about ridiculously small independent nations, as well as the Swedish radio show "Mosebacke Monarki". A similar plot was the basis of the German film Die Dubrow Krise (1969) that depicts a fictional East German town joining West Germany. Many problems that eventually plagued the actual reunification 20 years later were accurately predicted by the film.
Shirley's comment, "We'll fight them on the tramlines, we'll fight them in the local ..." is a take on Sir Winston Churchill's famous wartime speech, "We shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills..."
The last Duke of Burgundy was Charles de Valois, otherwise known as Charles "The Rash" or "The Bold" or "The Terrible. The 44-year-old Charles was killed in the Swiss War in 1477, and France annexed Burgundy. Burgundy's holdings outside of France passed to Charles' daughter Marie, and her marriage to an Archduke of Austria (who later became Maximilian I, Holy Roman Emperor) saw the Burgundian inheritance pass to the Habsburg dynasty.
In Spain -after a TV premiere (1973)- the film had a theatrical release (July 2015) 66 years later. Was released in 2 theaters (Madrid and Barcelona, Cines Verdi) in subtitled version and was only projected for 4 days.