Garum

Garum is a type of fermented fish sauce that was used in ancient Rome to season food. It was made by layering salted fish like anchovies in a jar and burying it in the sun so the fish would ferment and create a salty, fishy liquid. People in Rome added it to food to give it an umami flavor, like soy sauce. Even though it was created thousands of years ago, people today still use similar fermented fish sauces in their cooking, like Asian fish sauces.