Grateful American® Foundation

What was the Thornton Affair?

April 25th

paltoaltoApril 25, 1846 — The Thornton Affair began today when Mexican troops attacked a squadron of US dragoons commanded by Captain Seth Thornton near Fort Texas (modern-day Brownsville). The engagement left 16 US troops killed.

Capt. Thornton, who was knocked unconscious when he fell off his horse, was at first listed among those killed in the incident. The remaining 52 soldiers were held at Matamoros and later exchanged for Mexican prisoners. News of the incident reached Washington, DC two weeks later.

On May 11, then-President James Polk asked Congress for a declaration of war, maintaining that a state of war between the two nations already existed. Two days later, by overwhelming margins and with little debate, both houses voted to declare war.

Considered the last “strong” president until the Civil War, Polk is the last of the Jacksonians to sit in the White House.

Words of Wisdom

Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon the American soil.

— James Polk (11th US President from 1845-1849) asking Congress for a declaration of war, maintaining that a state of war between the two nations already existed.

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