Soy sauce, as a by product of soybeans(was first known as TaTeou), first invented in ancient China, is evolved from sauce and developed about two thousand years ago.
The original sauce is a costly condiment made from a fermented paste of fish, shrimp, and fresh meat, it first appeared in the Zhou Dynasty of ancient China and was only used by the Emperor. Later, soybeans have been providing the Chinese people with a meat alternative that is similar in flavor with highly nutritious, healthy, and inexpensive. Purely accidentally, people found the sauce kept a layer of brownish black color of juice after storing for a long time, its unique flavor and delicious taste attracts people. So people improved the sauce making process to specially brew the juice of sauce. The Soy sauce in its current form was created about 2,200 years ago during the Western Han dynasty of ancient China.