Human Intelligence Spying in the US-Mexican War

The US-Mexican War permanently reshaped the map of North America and marked a major turning point in the nation’s expansion. It was one of the nation’s first extended campaigns on foreign soil and human intelligence was a key element of American military success. The War was a short but consequential conflict in American history. Lasting roughly 26 months from 1846 to 1848 and fought across three theaters of operations, it carried US forces from northern Mexico to Mexico City and across New Mexico and California. By the war’s end, the United States had acquired nearly one million square miles of territory through the Treaty of Guadalupe Hidalgo, including what are now California, Arizona, New Mexico, and Texas, as well as portions of Colorado, Wyoming, Utah, and Nevada. Intelligence efforts proved critical to that success. Retired US Army historian and author of The Occupation of Mexico Stephen A. Carney explores the patchwork of traders, scouts, guides, couriers, friendly civilians, and paid informants who helped the US Army operate across vast distances and unfamiliar terrain. He pays particular attention to Winfield Scott’s campaign against Mexico City and to the organization of the Dominguez Spy Company, often referred to as the Mexican Spy Company. This presentation was recorded live at the International Spy Museum in Washington, DC, on June 10, 2026. Spy Museum's upcoming programs: https://www.spymuseum.org/calendar/ Follow us: Facebook:   / intlspymuseum   Twitter:   / intlspymuseum​​​​​​​   Instagram:   / spymuseum   SpyCast: https://www.spymuseum.org/podcast/ The Spy Museum does not endorse, approve, or support the opinions stated by guest speakers. Statements made by speakers do not represent the position or opinion of the International Spy Museum.