After the publication of "Tales of the O'Hara Family", John began work on his novel "The Boyne Water", a story of Protestant – Catholic relations during the Williamite War. He travelled back to Ireland, spending time in Derry and Belfast, to do research on the novel, which was published in 1826. That same year, a second series of "Tales of the O'Hara Family" was published, containing the novel, "The Nowlans".