John Douglas was an architect working in England in the mid- to late-19th century. He trained under Edmund Sharpe & Edward Graham Paley of Lancaster from about 1846. He was based in Chester, Cheshire, and was particularly associated with the estate at Eaton Hall. Some of his work is in English Gothic style, but he is especially known for his vernacular architecture. He practised on his own until 1884, when he went into partnership with Daniel Porter Fordham, who stayed with the practice until 1898. His second partner was Charles Howard Minshull, with whom he worked until 1909.