Maclaren was born in the highlands of Scotland on 2 March 1755, entered the army, and served in the American war under Generals Moore and Clinton.
His regiment returned to Scotland to recruit, and in 1783 Mr. Jackson's company produced his farce of the 'Coup de Main' at Edinburgh.
In 1794 he enlisted as a sergeant in the Dumbartonshire Highlanders, and went with them to Guernsey, where he was engaged to act as prompter in the theatre, and where several of his pieces were performed.
After the battle of Vinegar Hill he was discharged and went to London, where his dramatic writings afforded precarious support to his family till his death in 1826.
Prose.—‘A Minute Description of the Battles of Gorey, Arklow, and Vinegar Hill,’ 1798, 12mo, and ‘An Account of the Insurrection in Ireland,’ 1800.