Truth is pretty much all of Western Europe is Gaulish, especially by paternity (Spanish and Portuguese became brown because the R1B white men racemixed with Iron Age brown Spanish women)
The Dutch and North Germans are genetically closer to the ancient Gauls than the Irish are, even.
2/3 of the Saxons/Normans were R1B and Gaulish to begin with. Western Europeans are almost exactly the genetically same as they were 2000 years ago. Only I1A is a marker of genuine Germanic ancestry. The rest are just Celtic Gauls speaking a Germanic language. Romans were also Gaulish + Etruscans (also R1B) by paternity.