It's a Dutch brand.
At the start Frames were made by Pelizzoli (Ciocc) and Billato. Later they were made in Belgium too.
The PDM cycling team with among others Sean Kelly, Pedro Delgado, Greg Lemond, Raoul Alcala, Gert-Jan Theunisse, Erik Breukink and Steven Rooks rode on Concorde.
The better ones are really nice!