Nuevo Santander (New Santander) was a region of the Viceroyalty of New Spain, covering the modern Mexican state of Tamaulipas and extending into modern-day southern Texas in the United States. A history of Texas, commissioned by the U.S. government's Federal Writers' Project in 1934, noted that "The borders of New Santander did not stop at the Rio Bravo" (the Mexican name for the Rio Grande); and added that the borders "went north to the Nueces, near Corpus Christi, then west and north to the Medina, then south again on a line along Laredo to the eastern slopes of the Sierra Madres, deep in Mexico." 
|King of Spain|
• July 9, 1746 – August 10, 1759
• December 11, 1813 – September 29, 1833
• May 31, 1748 - April 8, 1767
|José de Escandón|
• July 7, 1821 - September 22, 1822
|Felipe de la Garza Cisneros|
|Historical era||Colonial era|
|Currency||Spanish colonial real|
|Today part of||Mexico United States|
Nuevo Santander was named after Santander, Cantabria, Spain, and settled by Spanish American colonists in a concerted settlement campaign peaking in 1748–1750. It fell under the jurisdiction of the Real Audiencia of Guadalajara in judicial matters, and in 1776 Nuevo Santander became part of the semi-autonomous Provincias Internas.
José de Escandón founded the colony in 1747. In 1755 Jiménez was founded which became the major town and capital of the colony. The state was subsequently renamed to Tamaulipas once Mexico gained its independence in 1821.
- Federal Writers' Project, The WPA Guide to Texas: The Lone Star State (U.S. Government Printing Office, 1934, reprinted by Trinity University Press, 2013)