Browsing through the deeper reaches of my chest freezer today, I came across a long-forgotten styrofoam container. Contained in that container was some Nattō (納豆), a fermented soybean product from Japan.
There are competing theories about the origin of natto, but one I favour theorises that it came about during a time of war in the 11th century. One day a powerful samurai was encamped with his men, when they were attacked while boiling soybeans for their horses. They hurriedly packed up the beans, and did not open the straw bags until a few days later, by which time the beans had fermented, turning into natto. Not being wasteful, the soldiers ate it anyway, and liked the taste, so they offered some to their lord, who also liked it. And the rest is history (or legend!)