In the early Middle Ages, they were making a sort of soy sauce in the Middle East. And amazingly, a recipe for it got translated into Latin.
Or maybe not so amazingly; medieval Europe was curious about the luxuries of the East. So Jambobinus (or maybe Jamboninus) of Cremona, a Spaniard living in 13th century Venice, translated 82 Arabic recipes and made them available to his fellow Europeans as " Liber de Ferculis et Condimentis " ("The Book of Dishes and Seasonings"). One of those recipes was for murri , the barley soy sauce.
Let us stop and marvel at this idea: soy sauce in medieval Europe. Soy sauce stains on damask robes, a jug of soy in the knight's saddlebag, barrels of soy aging in the old monastery cellar!
Unfortunately, it was not to be, because Jambobinus blew the translation. The recipe says to wrap loaves of raw barley dough with leaves to infect them with mold and then to let them rot for several weeks--typically in closed containers, so they'd stay damp as long as possible. Then, and only then, would the barley be mixed with water and salt to undergo more microbial action.
But Jambobinus skipped the whole mold-rotting phase of the recipe. He just said to let the barley dough dry out and mix it with water and salt. Anybody who followed his recipe would wind up with a ghastly sort of salty glue. No wonder that elsewhere in the manuscript he explained murri as "salty water."
So Europeans never took to adding soy sauce to their pate or sauerbraten or minestrone. And by the 15th century, murri had died out in the Arab countries themselves, no one knows why. End of story, until world trade reintroduced the soy sauce idea to the West centuries later.