The exact origins of chow chow relish are unknown, although a prominent theory is that it originated as a use for vegetables at the end of the season in the American South. As evidenced by a South Carolina recipe book, the roots of the food date to at least 1770.
Another origin theory places the origins of chow chow relish with immigrants from Nova Scotia who settled in New Orleans.
The origins of the name are also a mystery. One theory derives the word "chow" from the Mandarin Chinese word "cha," which roughly translates as "mixed." Another theory is that the name derives from the ingredient chayote, which is called "chow chow" in some areas of India.