Probably pre ww1, His sporran is Black Watch though his collar badges are not, though they are similar to the Royal Cypher, his glengarry badge has the general shape of the Argyll and Sutherland Highlanders His belt buckle normally would carry his regimental badge
A bit of an enigma, Not Canadian Black Watch either although their sporran is identical.
Perhaps post on the ww1 armed forces board with a name may help. Add any details that mey be on the reverse of the pic
James