Well, we call the people "Flamen" and they speak flämisch (engl.: flemish) - which makes for "flämisch gespleißte Sehne" in German (engl.: flemish spliced string). As far as I know it is indeed a different language thing. Flemish, as language, is more or less a sort of Dutch. Belgium is split in the Dutch (Flemish) and French speaking part, as indicated from my first graphic above. In former times Flandern (Flandria) reached more to the west as well - into todays France and I suppose it went and still goes into the Netherlands as well ...
Maybe V-Archer can clear all the linguistic and ethnic problems should he read this?!