For a very short period and as a way around steel rationing post war, some Bates Vergrandis frames were manufactured in Belgium.
Plum Vainquer is a shop in Ghent that made frames, if you ever go there the owner has a nice private Museum of bikes under the shop, ask if he will show it to you.
Doschesport were another frame shop in Ghent. Specialised in track frames, but built road and utility bikes too
Regards
Martin Coopland