Oysters have had a long association with stout. When stouts were emerging in the 18th century, oysters were a commonplace food often served in public houses and taverns. By the 20th century, oyster beds were in decline and stout had largely given way to pale ale.
The first known use of oysters as part of the brewing process of stout was in 1929 in New Zealand, followed by the Hammerton Brewery in London in 1938.
Modern oyster stouts may be made with a handful of oysters in the barrel, hence the claim of one establishment, the Porterhouse Brewery in Dublin, that their award-winning Oyster Stout was not suitable for vegetarians. Others, such as Marston's Oyster Stout, use the name with the implication that the beer would be suitable for drinking with oysters.