Great Britain & Commonwealth
The badge features the Black Watch Motto "Nemo Me Impune Lacessit" which translates into "No One Attacks Me With Impunity".
Manufactured in 1945 by Glisson & Miller, the size 4 suit easily fits a 6 foot stature. Though not easily seen in the photo, the broad arrow mark is partially hidden by the fold at the bottom seam of the tag. The many period appropriate repairs as photographed suggest this suit was used quite extensively but cannot be certain of when.
On the reverse, stamped in the top right corner is the official stamp for the "School of Tank Technology". Opened in November of 1943 the School was responsible for examining allied and enemy vehicles and writing intelligence reports.
The British H.L.I. were the only Highlander unit to be issued trews instead of kilts. Photographs from as late as 1931 suggest that their bagpipers continued to wear the traditional kilt. The Canadian H.L.I., unlike the British were kilted starting in 1935.