(via ) Ketchup and mustard are broadly recognized as being the two key condiments in the American fast food tradition, as if they were siblings from the same culinary mother. In this short explainer, Mental Floss‘ Food History details how this is not at all the case, drilling down on their very separate evolutions and revealing their different origin stories.
The history of ketchup and mustard includes a tomato ketchup pill sold as patent medicine, a personal mustard-maker to the pope, and an early variety of fermented fish-gut “ketchup” bearing little resemblance to the bottle of Heinz you may have in your fridge.