Geography time!
Jena is where Carl Zeiss established his optical works in 1846: and you’ll probably have seen the name on some lenses. It’s almost as close to Prague as it is to Berlin – and if your European geography is as poor as mine, you’ll have real trouble pinning the name onto a map. Go and look it up!
The Zeiss factory in Jena dwarfs the Chance Optical Glass Works in Birmingham (which you can see it you drive south from West Bromwich on the M5, waiting to be restored), and was where many important advances in optical design were made. As well as lenses, Zeiss manufactured the Contax rangefinder camera, the most serious rival to the Leica.
At the end of the Second World War, Jena was liberated by the Americans (who promptly shipped most of the Zeiss designers and technicians off) and was then designated as part of the Russian occupation zone (and the Russians shipped most of the equipment off to what became the Kiev factory).
This left a factory, a tradition, and some staff. Until the late Nineties, manufacture of lenses and other optical equipment continued, mainly using pre-War designs. Zeiss Jena lenses graced the fronts of Prakticas and Exaktas, and were the cream of East German lens manufacture. Because they shared the nearest thing to a universal lens mount ever made (the M42/Pentax/Praktica screw mount) they were often to be found on other brands of camera.
A rival Zeiss company was established in Oberkochen (with all the designers and know-how), and produced refined and upgraded optics: maintaining the Zeiss reputation for the very highest quality, and providing lenses for Hasselblad and the Yashica-made Contax SLRs. Oberkochen is even harder to find, and is heading towards the Swiss border.
It delights me that when Germany reunified, the Zeiss companies did the same… Like a feuding family that comes to its senses.