It could just be that a kilt is such a practical garment that similar garments keep popping up throughout history because they just make so much sense.

The garment we call a kilt today obviously (to me anyway) comes directly from Celtic culture. The combination of the arrangement of pleats, the flat apron, the direction of wrap all seem to be direct decendents of a Scottish (and therefore Celtic) design.

I hope that no one would be offended by the fact that many design ideas used in Europe were borrowed (some would say "stolen") from the Egyptians ( who, in their turn "borrowed" from the Babylonians and Phoenicians and others).

A culture would have to be completely isolated from the rest of humanity to be a truly "pure" culture. Such cultures tend to be rather backwards and stagnant.

Thanks to the Celts, the Scots, the Brits and the Irish -- and, more recently, a guy name Steven, the modern kilt is a vast improvement over similar garments that came before.