Thornton Affair – It’s mostly how Texas got so big.

Time Before Now – April 1846 – The first deaths from the Irish potato famine were reported as a third of Ireland’s potato crop had failed a year earlier.  Massachusetts inventor Elias Howe requested a patent for the first American lock-stitch sewing machine (left) and a group of beleaguered Mormons began their trek west from Nauvoo, Illinois.


April 25, 1846

On this day a land deal gone bad turned into a war.  Known as the Thornton Affair, it was only the latest sound of gunfire along the U.S. border with Mexico.  

Actually beginning a year earlier, U.S. President James Polk’s offer to buy a contested piece of real estate between the Neuces and Rio Grande rivers was rebuffed. (Right, area in red)  The Mexican government was in no mood to sell, still fuming over the American annexation of Texas. 

Polk promptly sent a military contingency to the border under the command of General Zachary Taylor.  Polk’s critics contending he was spoiling for a fight.  And it didn’t take long to find one.  There were soon reports of Mexican forces crossing the Rio Grand River.  A local guide advised investigating an old hacienda.  Acting on that advice, Taylor (right) sent Captain Groghan Ker down river and Captain Seth Thornton upstream. 

 By sundown Captain Thornton’s Dragoon company of approximately 80 men was soon overwhelmed by 1600 Mexican soldiers under the command of General Anistasio Torrejon, all camped in the area of the hacienda.  It was unclear whether Thornton was ambushed on information by a false flag or the victim of a purely accidental engagement. 

The lopsided battle lasted several hours into the night but Thornton was forced to surrender.  In all, 11 Americans and an unknown number of Mexicans were killed.  Six  more Dragoons were wounded and the rest, Thornton and most of his officers included, were marched several miles south to Matamoros as prisoners of war. 

American blood has been shed on American soil,”  President Polk (left) asserted.   Mexico contended it wasn’t American soil at all; it was Mexican soil and Mexicans had also died.  The encounter, however, provided Congress with a rationale to declare war on its southern neighbor 18 days later.

Taylor and Torrejon didn’t wait for the official declaration.  They clashed two weeks later at the Battle of Palo Alto near Brownsville, resulting in an American victory.  A prisoner exchange  following Palo Alto freed Captain Thornton.

Artist’s rendering of the Battle of Palo Alto

The actions by Congress also gave American forces permission to take over Santa Fe and Alta California Territory, fulfilling another of the President’s fondest wishes for U.S. expansionism.   Popular with many, it was equally unpopular with many more.

Artist’s rendering of the surrender of Mexico City

Two years later, the Treaty of Guadalupe Hidalgo ended the bloodshed. The U.S. paid Mexico $15 million in war damages as well as assuming $3.25 million in debt Mexico owed American citizens.   A total of 13,283 U.S. soldiers died in the conflict and another 4,152 were wounded.   Mexico’s war dead totaled more than 10,000 regular soldiers and an unknown number of civilians, perhaps as high as 20,000. 

Criticism of the war also intensified the already hotly debated issue of slavery and is now considered a precursor to the Civil War.  Former president John Quincy Adams, then a member of the House of Repre-sentatives from Massachusetts, was a strong opponent of “Polk’s War” as was a newly elected Congressman from the 7th District of Illinois, future president Abraham Lincoln. (Left)   It did a great deal, however, for the political fortunes of  President Polk’s successor to the White House, General Zachary Taylor.

In addition, the conflict was the perfect proving ground for a number of Civil War generals, both North and South.  Most didn’t much care one way or the other about the annexation of Texas.  Ulysses S. Grant (left) was not among them.   “Morally unjust,” Grant wrote in his memoir, undertaken to expand slavery and laregly responsible for the “Southern rebellion.”  “Nations, like individuals, are punished for their transgressions.”

 Polk may have been an individual recipient of Grant’s prediction.  Honoring his pledge to be a one-term president, Polk refused to run for reelection in 1848.  Taylor, the general he’d helped make famous, won nearly 48 per cent of the votes in a three-way race.

The ex-president, a slave holder much of his adult life, retired with his wife to Nashville, Tennessee.   He was lavishsly praised and widely admired in the Deep South.  He died three short months later, June 15, at age 53, most likely of cholera contracted on the riverboat during his trip to Nashville.

Taylor may have suffered a similar fate, serving as President for about 15 months.  He died July 9, 1850,becoming ill after consuming “copious amounts of cherries and iced milk” at a fundraiser for the construction of the Washington Monument.  He was 65. 

Artist’s depiction of  Taylor’s death

The official cause of Taylor’s death was generally listed as “stomach disease.”  Doctors of the day termed it cholera morbis, an all-purpose diagnosis for a variety of digestive disorders.  Hair sample analysis years later put to rest suspicions of murder by poison.   Scientists today suspect it was salmonella or other food borne illness caused by the early Capital city’s unsafe drinking water. 

 Unfortunately, the hapless Captain Thornton failed to survive the war altogether.  Falling ill in the summer of 1847, he was still ailing as the Americans made a final assault on Mexico City.   He chose to lead a far flung reconnaissance mission on Mexican artillery and was killed by a cannonball.

Palo Alto Battlefield National Park , 7200 Paredes Line Road, Brownsville, Texas, was established in 1992.  It includes Rancho de Carricitos, the site of Thornton’s battle, as well as Zachary Taylor’s Fort Texas and the Palo Alto Battlefield.  Resaca de la Palma, much now within the Brownsville city limits is undergoing the construction of new trails.  Regular hours for the  park’s visitors center are 8 to 5 daily.  The overlooks and trails are open 8 to 4:30. 

The park is closed Thanksgiving, Christmas and New Years.  There is no admission fee.  For more information go to Palo Alto  Battlefield National Historical Park (U.S. National Park Service), call the Visitor Center, (956) 541-2785 Ext. 333 or park headquarters – (956) 541-2785 Ext. 221.

In accordance with CDC guidelines most facilities in the national parks are closed.  Outdoor spaces in some parks remain open to the public, however.  For the most current information on this and other National Parks, go to the individual park sites.

© Text Only – 2020 – Headin’ West LLC  – All photos – public domain or fair use.

*Head On West strives for historic accuracy and uses a number of sources considered reliable.  When research differs on significant facts, the various points of view will be cited.