The Romans were probably the first to produce mustard by mixing unfermented grape juice with ground mustard seeds. It's used in recipes in the Roman cookbook 'Apicus' as far back as the 4th and 5th centuries.
In the 1690s the Chinese mixed pickled fish and spices and called it koe-chiap or ke-chiap. By the early 18th century this had been discovered by British explorers who called it 'ketchup'. The name was then applied to the tomato-based version that appeared around a century later.
You can put mustard and ketchup in these very cool condiment crayons. Of course you can.