'Poverty and oysters always seem to go together'.
Oysters have been savoured in Britain since Roman times. Shells have been found at many archaeological sites, with the Roman fort and Amphitheatre in Richborough as the most symbolically important one, and stretching as far north as Hadrian’s and the Antonine walls. Before the Romans came, the Britons regarded shellfish as something to eat when there was no fish or meat to be had. The little molluscs weren't sought after until the Romans started to farm them and even export them live to Rome, where they were considered a delicacy.
When the Romans withdrew and the Saxons invaded in the 5th century, so a rich culinary culture disappeared, which included the oyster farming. It would take centuries for the oyster to become popular again and the first recorded appearance is to be found in a 14th century cookery manuscript by the Master Chef of King Richard II.
Throughout the Medieval period the church imposed a number of days where one should eat fish rather than meat. In fact, for a third of the year, eating meat was forbidden. Therefore the mixing of fish and meat in dishes only became popular later in the 16th century and an early 17th century cookbook gives the recipe for roasting mutton with oysters.