Celtic Place-Names in Europe
To answer these questions fully would take us (for the purposes of this volume) too deeply into philological discussions, which only the Celtic scholar can fully appreciate. The evidence will be found fully set forth in de Jubainville's work, already frequently referred to. The study of European place-names forms the basis of the argument. Take the Celtic name Noviomagus composed of two Celtic words, the adjective meaning new, and magos (Irish magh) a field or plain.15 There were nine places of this name known in antiquity. Six were in France, among them the places now called Noyon, in Oise, Nijon, in Vosges, Nyons, in Drôme. Three outside of France were Nimègue, in Belgium, Neumagen, in the Rhineland, and one at Speyer, in the Palatinate.
The word dunum, so often traceable in Gaelic place-names in the present day (Dundalk, Dunrobin, &c.), and meaning fortress or castle, is another typically Celtic element in European place-names. It occurred very frequently in France—e.g., Lug-dunum (Lyons),Viro-dunum (Verdun). It is also found in Switzerland—e.g., Minno-dunum (Moudon), Eburo-dunum (Yverdon)—and in the Netherlands, where the famous city of Leyden goes back to a Celtic Lug-dunum. In Great Britain the Celtic term was often changed by simple translation into castra; thus Camulo-dunum became Colchester, Brano-dunum Brancaster. In Spain and Portugal eight names terminating in dunum are mentioned by classical writers. In Germany the modern names Kempton, Karnberg, Liegnitz, go back respectively to the Celtic forms Cambo-dunum, Carro-aunum, []Lugi-dunum, and we find a Singi-dunum, now Belgrade, in Servia, a Novi-dunum, now Isaktscha, in Roumania, a Carro-dunum in South Russia, near the Dniester, and another in Croatia, now Pitsmeza. Sego-dunum, now Rodez, in France, turns up also in Bavaria (Wurzburg), and in England (Sege-dunum, now Wallsend, in Northumberland), and the first term, sego, is traceable in Segorbe (Sego-briga) in Spain. Briga is a Celtic word, the origin of the German burg, and equivalent in meaning to dunum.
One more example: the word magos, a plain, which is very frequent as an element of Irish place-names, is found abundantly in France, and outside of France, in countries no longer Celtic, it appears in Switzerland (Uro-magus now Promasens), in the Rhineland (Broco-magus, Brumath), in the Netherlands, as already noted (Nimègue), in Lombardy several times, and in Austria.
The examples given are by no means exhaustive, but they serve to indicate the wide diffusion of the Celts in Europe and their identity of language over their vast territory
