Mexico, formerly known as New Mexico, is a city in Audrain County, Missouri. The population was 11,543 at the 2010 census. It is the county seat, home to the Missouri Military Academy, and annually hosts the Miss Missouri Pageant. The micropolitan statistical area consists of Audrain County. It is a part of the Columbia, Missouri metropolitan area.
Mexico was laid out as "New Mexico" in 1836 and was a major stop for settlers heading to the Republic of Texas (thus the name "New Mexico"), and it became the county seat under its present name in 1837. The word "New" was dropped after the Mexican War that saw Texas become a part of the United States.
There is an apocryphal story about the name. When a University of Missouri student, who was questioned on radio, was unable to give an account of her hometown's name, the question was put to L. Mitchell White, then editor and publisher of the Mexico Ledger: "'The first settlers found a wooden sign along the trail. It pointed southwest, and on it had been painted Mexico.'" To avoid unnecessary labor, the sign was left in place.