Izaak Walton first published his popular work The Compleat Angler in 1653. Charles I, the king of England, had been executed just four years earlier after almost a decade of civil war, and the king’s opponents had also abolished the Church of England. Long hailed as a primary inspiration for the modern conservation movement, most scholarship on the Angler has either ignored or muted the political context of Walton’s most famous book. However, the Angler is permeated with religious and political polemic. Revised multiple times before the author’s death, Walton amplified and extended his arguments in response to changes in law, politics, and religion. The present essay argues that when read alongside his other works and related literature published during these same years, the successive editions of Walton’s best seller emerge as one of the clearest, most consistent declarations of Anglican royalism in the mid-seventeenth century.