McCulloch did much to popularize Scottish landscape painting and, so fashionable were his pictures during his lifetime, the engravings of his Highland subjects sold in great numbers. His paintings of the remote areas of Argyll and the West Coast were amongst the first depictions of what was then known as North Britain to be widely circulated. Like his contemporary and rival Sam Bough he did not have extensive artistic training. He worked for a short time in 1820s with the Glasgow-based landscape painter John Knox and during that decade his paintings show the influence of that artist. However his mature work is distinctively his own and he became particularly adept at the aerial perspective of distant mountains. His landscapes often include crumbling strongholds, and despite his romantic vision, usually depict an actual place.