Earlier this year I visited The Haithabu museum in Schleswig, and there was a model of an oarsman wearing a tunic, and bare legged.

There are arguments as to the extent to which some Vikings/Northmen went bare legged; which could be an argument for some such style of dress today in Scandinavia.

As for the word kilt, right throughout much of Scotland, as with northern England there are traces of Scandinavian in the local tongue, place names.

In my younger days I have heard the word kilt used in the following way 'kilted up', as a reference to a woman tucking her long skirts into her waistband so as to free her legs for walking/work. This suggests that the actual root-is in the expression 'fold': which would accord both with my example, and putting the pleats into a belted plaid.

James