I have heard the custom of wearing nothing beneath a kilt referred to as “going regimental.”
The modern kilt is certainly a . . . well . . . modern invention, but the so-called great kilt certainly isn’t. The question is whether the tradition of wearing nothing under a modern kilt originated as a throwback to the great kilt, or was a later innovation. It was Sir Walter Scott who developed the modern kilt for a royal visit wasn’t it? Did he specify that it was to be worn “regimental”?
And what do people who do wear underwear with a kilt wear? I’d like to own a kilt someday (especially if I ever get married) and I’d feel much sillier if my kilt flew up in a dance and I was wearing Fruit of the Loom briefs underneath than if I was wearing nothing at all!
My preference is plain black briefs. I have observed some Kilt-wearers taking part in very physical activity (such as caber tossing) wearing something like bike-shorts.
It’s also a good idea for your shirt to be longer than you might wear with pants so that the top of the kilt doesn’t chafe at the waist… speaking of which… regimental might have some tradition behind it… but that heavy weight wool can be a mite scratchy. :eek: I’d go with the briefs.
A lassie took me to a ball
And it was slippery in the hall
I was afeared that I would fall
For I nae had on no troosers
The Simpsons, of course, have explored this question.
Oh but doesn’t the laddie have a proud look on his face. You know it was a cold day 
Aye, my husband goes commando when needed, but he also wears the bike shorts when marching in the parades, he didn’t want to catch a breeze and scare some child that might have been close by :eek: Everyone marching the 13 miles wore bike shorts, and thanks for making me laugh since St. Patrick’s Day is coming up and I need to get his kilt and gear ready to go (bike shorts included). 
For my wedding I wore dark briefs under my kilt - as noted small children, dancing, and an absense of underclothing do not mix 
As a student I used to wear a kilt for formal dining in nights at the OTC (Officer Training Corps) and - being military and traditional - I would normally go commando. The hazard then was so called “friends” crawling around the floor with a camera :smack:
Sung to the tune of a familiar bagpipe song (the name of which escapes me), the second and third lines in your best imitation of a bagpipe drone:
What does a Scotsman wear under his kilt?
A wang
A wang
I always respond that nothing is worn beneath my kilt…
It’s all in perfect working order!
Cite. 
LOL for ten minutes! Yes, I’ve seen it before but HA! The look on that guy’s face is hilarious! Thanks for the laugh. 
I’ve always wondered why so many women feel that it’s okay to come up and ask me what I’m wearing under my kilt. If I approached a woman I didn’t know and asked what she had on under her skirt, I’d probably get slapped. Why is it okay for her to do it to me?
Damn, those separatists are getting hardcore!
It isn’t okay, but people think it is because of decades of smirking, childish penis- or testicle-related jokes whenever people talk about kilts.
You want the straight answer? It’s pretty simple – because men are bigger and stronger, and one Hell of a lot more likely to commit violent rape.
And a different straight answer: Part of what they are asking (whether they phrase it this way or not) is exactly what the OP was asking Cecil: “I’ve heard that its normal / traditional to wear northing under your kilt. Is this true?”
I can’t speak for a Scot but as for the Mick’s, I’ll tell you a gentleman never reveals what’s under his kilt unless he plans to use it. :dubious:
My favorite story came from a friend, who claimed to be 11th (if I recall correctly) in line for the Scottish throne, if the British ever give it back.
Question: “What do you wear under your kilt?”
Answer: “Your wife’s lipstick.”
The Scots are British. Presumably, he meant “the English”. But that still leaves a problem, because the House of Windsor traces back its ancestry to the House of Stuart, which was Scottish. Now, it is true that the House of Stuart was kicked out, but, this is only true to the extent that Roman Catholics were excluded from the royal line. The person chosen (the Electress Sophia of Hannover) was the closest Stuart relation who was a Protestant. (She died before it became necessary for her to take the throne, so her son George received it instead.)
And I don’t think the bulk of the Scots are ready for a Roman Catholic monarch to this day.
Anyway, was your friend from the senior line of Stuart pretenders, who have the unfortunate problem of being descended from an uncle-niece marriage, or from the junior line?
Wow!! Well then, I wonder…?? “Am I the only one; who thinks Kennedy is what a Scot keeps under his kilt ??” 
I’ve never met the gentleman, nor do I claim anywhere near your knowledge of the sucession lines. However, I suspect that the person in question was just blowing smoke. I’ve met many of that type at highland games and ceilidh’s. They love to tell tall tales. Kinda like how at many VFW post s you’ll eventually run into a “special-forces-secret-commando-ninja” who “can’t talk about it”, but does.