Nueces County was formed in 1846 and named for the river on its northern edge

The county was organized in 1846, with Corpus Christi as the county seat. The name comes from the Nueces River that forms the county's northern boundary. Spanish and Irish settlers had already been in the area for decades before the county was created.

The Spanish explorer Alonzo Alvarez de Pineda is believed to have reached Corpus Christi Bay in 1519. In the 1820s, Irish colonists established settlements along the Nueces River under land grants from Mexico. The 1850 census counted only 689 people in the entire county.