When you get in a taxi in Glasgow, Scotland, and ask to be taken to this or that particular bicycle shop, you sometimes get a stream-of-consciousness response from the driver that goes something like this:
"Aye! - I was a cyclist - a fair while ago, mind - I had a Flying Scot bike, by the way - hand-built - with they French gears - made in Luxembourg or somewhere daft - it was a lovely wee machine ..."
It doesn’t matter whether the taxi driver’s Cyclo Benelux derailleurs were made in Birmingham, England (as they were) or made in ‘somewhere daft’ like the Principality of Luxembourg (as they were decidedly not), there was no getting away from the fact that they were FRENCH gears.
As the taxi driver has correctly detected, the spiritual home of the derailleur is France - and this is not just because of the inherent, unfamiliar, Frenchness of words like ‘derailleur’ (not often pronounced in Glasgow - hence the simpler term ‘French gears’) and brands like ‘Huret’ (pronounced in Glasgow to rhyme with ‘turret’). It is because of half a century of relentless innovation in France that eventually led to the birth of the derailleur bike as a mass market item.
There were three giants of this period:
Browse the derailleurs from France...
Where you see a red link, this is for a derailleur model dating from 1950 or before, which I do not (yet?) have in my collection - but for which I do have some kind of real and relevant documentation.