who can wear a kilt?
Even though you are unlikely to offend anyone by wearing a kilt that isn’t associated with heraldry, military service or an organization, how you behave in a kilt could be offensive, and not just to Scots. Make sure that you remember to keep your legs closed when you’re wearing a kilt and to be modest. That rule applies to Scots, too!

Can You Wear A Kilt If You're Not Scottish?
Kilts are associated with Scottish and Irish heritage and have a long tradition as a part of Celtic culture. For Irish and Scottish gents, kilts can be a way to show off pride for their nationalities, and that leads to an important question–is it offensive for non-Scots to wear kilt?