What is "pickled herring"

n. herring preserved in a pickling liquid (usually brine or vinegar)

Pickled herring, also known as bismarck herring, is a delicacy in Europe, and has become a part of Baltic (, , ), Nordic (inlagd sill), Dutch, German (Bismarckhering), Czech (zavináč), Polish (śledzie w occie), Eastern Slavic, Scottish and Ashkenazi Jewish cuisine.

Most cured herring uses a two-step curing process. Initially, herring is cured with salt to extract water. The second stage involves removing the salt and adding flavorings, typically a vinegar, salt, sugar solution to which ingredients such as peppercorn, bay leaves and raw onions are added. In recent years, other flavors have also been added, due to foreign influences. However, the tradition is strong in Denmark, Sweden, Finland, Norway, The Netherlands, Iceland and Germany. Onion, sherry, mustard and dill are some of the traditional flavourings.