Mustard originated from the mustard plant, a member of the brassica family that also includes vegetables like broccoli, Brussels sprouts, and cabbage. The ancient Greeks and Romans were among the first to process mustard seeds into edible mustard condiments and sauces. They would grind up the pungent mustard seeds and mix them with wine, vinegar, olive oil, and other flavorings.

In the 4th century AD, the Romans introduced mustard to Gaul (modern day France), where Dijon-style mustard was born. French monasteries helped keep mustard-making traditions alive through the middle Ages by growing mustard plants and grinding the seeds into the now-signature Dijon mustard. The Dijon region of France remains a prominent mustard producer to this day.

Also during the middle Ages, mustard was also used for medicinal purposes. Mustard Comes to the New World.

French settlers brought mustard to North America in the 16th century. English colonists who settled in the American South cultivated mustard seeds and began making their own styles of mustard around the 18th century. Small local mustard companies sprang up over the next two centuries across the United States and Canada.

In the 18th century, mustard began to be produced on a larger scale. The first commercial mustard mill was established in Dijon, France, in 1777. Soon after, mustard production spread to other parts of Europe and the United States.

In the 19th century, the popularity of mustard continued to grow. It became a common condiment for hot dogs, sandwiches, and other foods. Companies like Grey Poupon and Colman's emerged and became famous for their mustard products.

But, mustard was first mass-produced in the U.S. starting in the early 1900s. Companies like French's, Plochman's, and Gulden's took mustard from a local product made by families and monasteries into a national phenomenon.