Alfred Borst ran a factory he called his Albo Works in Shöenbach, Czechoslovakia in the early part of the 20th century. They produced all manner of chordophones, both fretted and unfretted mainly for export to the rest of Europe. As well as the Albo brand, a lot of the instruments they produced were unbranded for other distributor to brand, or not as they desired. 

One Ukulele brand they definitely made was Radiotone, (there were also US made Regal Radio Tone - with a space - Guitars which are nothing to do with this). This was a Dallas brand of the 1930's and these ukuleles were unusual because they were all steel strung archtop Tenors. This was the only Radiotone Ukulele in the Dallas catalogue but it is possible that this model may have gone under different names elsewhere in Europe, and that the manufacturer may have made other Ukuleles for the British market using different brand names? (I would guess that they made some of the Keech long scale Ukuleles; which were also distributed by Dallas). 

The business and factories didn't survive WW2, (unless you count Framus?)