http://www.eupedia.com/europe/european_y-dna_haplogroups.shtml
61 % R1b, probably mostly celtic, but some germanic too, it would be interesting to know what subclades, we could see how many 'Belgae' survived
12 % I1 so certainly some germanic too
Well, The Netherlands is about 50% R1b but I don't see them as Keltic. They're probably one of the most Germanic nations. These haplogroups don't always say much about ethnicity I think.