The Thornton Affair (also called The Thornton Skirmish in some texts) was a primary motivator in causing President Polk to ask for a state of war against Mexico in 1846, sparking the Mexican-American War.

The incident is clouded by over a century and a half of propaganda, half truths, and great exxagerations by the participants on both sides. However, it can be ascertained that the event occurred sometime around dusk on April 25, 1846, and continued in the early hours of April 26, 1846.

A company of seventy United States Dragoons commanded by Captain Seth Thornton was ordered to scout an area about twenty miles northwest of Brownsville, Texas. On the 25th, the Dragoons, acting on the advice of a local guide, investigated an abandoned hacienda. What precisely happened after this point is not entirely clear; however, some two thousand Mexican soldiers under the command of Colonel Anastasio Torrejon were encamped in and around the hacienda, and a firefight occurred. Although the Americans, by all accounts, fought ferociously, they were greatly outnumbered, and were forced to surrender after several hours of skirmishing.

During the skirmish, some sixteen American troopers were killed, with an unknown number of Mexican dead. Thornton and many of his officers were taken prisoner, and held in Matamoros, Mexico as prisoners of war. Upon learning of the incident, President James K. Polkasked for a declaration of war before a joint session of the United States Congress, summing up the need for war by stating:

"American blood has been shed on American soil".

On May 13, 1846 Congress declared war on Mexico despite protestations by the Mexican government that Thornton had crossed the border into Mexican Texas, a border that Mexico claimed began south of the Nueces River, and which the United States claimed began several mikes to the south at the Rio Grande. The ensuing Mexican-American War was waged from 1846-1848, and witnessed the loss of many thousands of lives and nearly two thirds of the territory of Mexico.

See Also

References

Bauer, K. Jack "The Mexican-American War 1846-48"