[3] The county was named after James Webb (1792–1856), who served as secretary of the treasury, secretary of state, and attorney general of the Republic of Texas, and later judge of the United States District Court following the admission of Texas to statehood.

Webb County is the only county in the United States to border three foreign states or provinces, sharing borders with Coahuila, Nuevo Leon, and Tamaulipas.

Much of Webb County history is based on the prevalence of ranching in the 19th century and continuing thereafter.

The Webb County Heritage Foundation is a nonprofit organization that seeks to preserve documents and artifacts of the past to guarantee that the regional history is not lost to upcoming generations.

In 2015, the foundation, headed by President James E. Moore, presented Heritage Awards to such local notables as the artist Janet Krueger, journalist Maria Eugenia Guerra, and Laredo Community College art instructor Martha F. Fenstermaker (1943-2014).

The racial makeup of the county was 99.8% White and 0.2% Black or African American.

[15] Despite its long-term Democratic streak, since 2016 Webb County has been trending more towards the Republican party, due to Donald Trump attracting more Hispanic voters.

On May 9, 2005, the Texas Education Agency ordered the closure of Mirando City ISD.

The district closed on July 1, 2005, and all students were rezoned to Webb CISD schools.

[18] The private Holding Institute is a former United Methodist boarding school operating as a downtown Laredo community center.