This article discusses major developments in British marine (and to a lesser degree freshwater) fishing and fish trade between ad 1050 and 1550. Much information derives from study of fish bones recovered by archaeological excavation. Historical evidence is also important, as is information regarding human diet based on stable isotope analysis of skeletal remains. By combining these sources it is possible to infer the initial growth of marine fishing (especially of herring, cod, and related species), the emergence of long-range fish trade, and the late-medieval reorientation of traditional fisheries to harvest ever more distant grounds. Concurrently, it is possible to document a declining catch of freshwater fish, as they became more exclusively associated with elite consumption.