The word mustard is thought to come from two words: “mustum,” a Latin word for young wine, which is called must, and “ardens,” a Latin word for hot. It was a hot condiment made by grinding mustard seeds up with must to form a paste, and still today as a condiment made from mustard seeds (whole, ground, or cracked) and mixed with a liquid like water or lemon juice to create a paste, is used around the world, from India and Bangladesh to the Americas, to Africa and Europe. It’s considered one of the most popular condiments in the world.
Mustard was cultivated in the Indus Valley more than 1500 years B.C.E., but likely first found use as a table spice with the Romans, who would have exported it, as by the 13th century, Dijon, France, had become known for mustard manufacturing, a tradition that would continue into the 18th century when Grey-Poupon’s partnership was formed and mustard manufacturing was automated. It was also popular in medieval England, where it was favored because it stored so well. Ground mustard mixed with flour and cinnamon and/or horseradish was lightly moistened and rolled into balls that were dried. They had enormous advantage because they would not spoil or lose their flavor if stored in a cool, dark place and could then be ground up again for use as a seasoning at the table.
By the 16th century, earthenware mustard pots began to appear on tables, where the ground mustard could be mixed on the plate to an individual’s tastes, and they began to accompany cruets of vinegar, wine, and/or oil, which were commonly mixed with the ground mustard. By the late 1700s, castor sets with silver or glass bottles adorned tables, sometimes simple sets with just salt and pepper shakers but often larger and more elaborate sets with containers for vinegar and oil as well as sugar shakers and mustard pots. By the 19th century, mustard pots were rarely found separate from a larger cruet set that decorated fashionable dining tables and sideboards. The trend would begin to decline rapidly in the 20th century however, particularly after French’s introduction of their yellow mustard at the 1904 World’s Fair in St. Louis.
In terms of value, it depends greatly on the material and the age. Silver mustard pots made by a well-regarded silversmith will have strong value, of course, as will standalone jars or pots, particularly if they are early and in good condition. Cruet sets have been a tougher sell in recent years because they are rarely used now and many people are unfamiliar with them, while the individual pots often do better because they can be repurposed in some way.