 James was of a line of esteemed bell-wrights, blacksmiths, and engineers, with a brother (also named Robert) who served as blacksmith for the Duke of Argyll at Inveraray Castle.Napier was educated at the burgh school where he took an interest in drawing, which reflected in his later life in an interest in painting and fine arts.Against his father's hopes that he would become a minister in the Church of Scotland, he developed an interest in the family business.