Born in Paisley, Renfrewshire, Scotland, but living largely in Aberdeen, MacGregor used the pseudonym McIntosh (along with its variants J. T. MacIntosh, and J. T. M'Intosh) as well as "H. J. Murdoch", "Gregory Francis" (with Frank H. Parnell), and "Stuart Winsor" (with Jeff Mason) for all his science fiction work, which was the majority of his literature, though he did publish books by his own name.
S-a născut în Paisley, Renfrewshire, dar a trăit cel mai mult în Aberdeen, MacGregor a folosit pseudonimul McIntosh (alături de variante ca J. T. MacIntosh sau J. T. M'Intosh) dar și "H. J. Murdoch", "Gregory Francis" (împreună cu Frank H. Parnell) și "Stuart Winsor" (cu Jeff Mason) pentru toate lucrările sale SF, care formează majoritatea operei sale literare, for all his science fiction work, which was the majority of his literature, deși a publicat și cu propriul său nume.