When, where, and by who was ketchup invented?
here’s a start:
Ketchup, by whatever spelling you choose, has been around for awhile. I believe it’s a Chinese or Malaysian word originally. The word was used for a sauce compounded from various edibles, seafood being the main one. When the idea came to America, local produce entered the recipe, which might’ve included peppers, onions, mushrooms, walnuts and by then the tomatoes previously thought poisonous. Worchestershire sauce or fish sauce is probably closer to the original than the red stuff we know all too well.
FWIW
Ketchup is a Chinese word in origin. In the Amoy dialect of southeastern China, koechiap means ‘brine of fish.’ It was acquired by English, probably via Malay kichap, toward the end of the 17th century, when it was usually spelled catchup (the New Dictionary of the Canting Crew 1690 defines it as ‘a high East-India Sauce’). Shortly afterward the spelling catsup came into vogue (Jonathan Swift is the first on record as using it, in 1730), and it remains the main form in American English. But in Britain ketchup has gradually established itself since the early 18th century.
AKA Tomato sauce, pasta sauce, ketchup,… etc.
To answer the OP … No one seems to know.