Undies under the Kilt

[Woodsheal]

I remember reading somewhere many years ago that it was for pracitical purposes during battles in those days;
One wouldn;t be 'Caught with one's pants down" so to speak, during a surprise attack, when answering nature's call. Plus in crossing often waist deep streams etc. one simply hoisted up the kilt. No wet trousers or underwear to worry about afterward.

I wouldn't say that there was ever a conscious decision on the part of Highlanders along the lines of, "We're not going to wear underwear!" And the reason is (speaking about the 'historic" period now, pre-1800) Highlanders WERE actually using the same underwear as European men elsewhere, that being long shirt tails. Separate drawers came later.
The underwear of that period for trouser and britches wearers - as well as the kilted - was your shirt tails tucked between your legs. Some even had buttons to facilitate this practice (shirt tails were knee length in those days).
So, later when underwear/drawers evolved as a separate garment (early 1800's), the backwards Highlanders simply clung to their old practice of their shirt tails being their only undergarment....