"After about 400 BC, Celtic artisans began seeking inspiration in Greek and Etruscan art, choosing certain motifs and breathing into them a new and distinctive Celtic spirit. Plant imagery and circular ornaments, demons’ grimaces and mythical creatures adorned jewelry and weapons, horses and wagons. Motifs are often more sculptural, more elegant and more individual than the originals that inspired them, and they combine into artifacts that have an unmistakable style. Depending on the incidence of light and the viewer’s imagination, hidden hideous features and grotesque faces can also be discerned. The new style is also seen quite strikingly in coins that are a strange and unique adaptation of their Greek and Roman models. Celtic artifacts reflect the high technical skills of their makers, whose toolboxes often already contained instruments similar to the tools used by artisans today."
Increasingly, "the Celts, Etruscans, Greeks and Romans exchanged both goods and ideas in the region of present-day Switzerland. This is attested to by imported luxury goods and by the use of writing, with inscriptions using the north Etruscan alphabet (or in other places, Greek or Latin letters) The Celtic languages were part of the Indo-European language family. Continental Celtic languages were spoken on the European mainland and by the Galatians in Asia Minor. They are now extinct. Insular Celtic languages, however, are still spoken in Ireland and in parts of Britain and France." Landesmuseum Zurich
The grave marker below is an Celtic inscription in north Etruscan letters: teromui kalui