This subject was covered a number of years ago in at least two threads:

http://www.xmarksthescot.com/forum/f...h-kilts-33489/

http://www.xmarksthescot.com/forum/f...25/index2.html

Most likely, the adoption of the kilt by Cornish nationalists came around the turn of the 20th century, as mentioned in both threads.

Regards,

T.