In August 1845 the 5,000 man American Army under General Zachary Taylor encamped at Corpus Christi, Texas as the "Army of Observation" when the American annexation of Texas threatened war with Mexico. In April 1846, Taylor marched his army to the Rio Grande as the "Army of Occupation" and hostilities commenced. There, Taylor constructed a large, earthen fort across the river from the town of Matamoros. On Friday, May 1st, Taylor marched the bulk of his army east 26 miles to his supply base at Point Isabel leaving about 500 men of the 7th US Infantry regiment under Major Jacob Brown and companies of the 3rd and 5th US Artillery regiments under Captain Allen Lowd to defend the unfinished fort. In addition to its garrison, the fort housed handfuls of wounded soldiers, women, children, civilians, and Mexican prisoners. Taylor named the structure Fort Texas.
On Sunday, May 3, 1846, the Mexican Army, across the river, launched a cannon barrage against the fort. Inside Fort Texas, the 7th Infantry's company commanders under the direction of engineer Captain Joseph K. F. Mansfield busily supervised the continued construction of bombproofs while the artillerymen on the parapets returned fire with their small assortment of 18 and 6-pounder cannon. The Mexican shells did little damage at first as they thudded harmlessly into the dirt sides of the fort - harmlessly except for one shell that hit and killed infantry sergeant Horace A. Weigert. The Americans knocked out a Mexican gun emplacement on the bank at Matamoros then reduced their fire in order to preserve their ordnance.
There were ten companies of 7th Infantry at Fort Texas: Co A under Gabriel Rains, Co B under Francis Lee, Co C under Theophilus H. Holmes, Co D under Richard H. Ross, Co E under Dixon Miles, Co F under Richard C. Gatlin, Co G under Washington Seawall, Co H under Edgar S. Hawkins, Co I under Gabriel Paul, and Co K under Daniel P. Whiting. All the company commanders were captains except for Paul who was a 1st Lieutenant filling in for Captain Stephen W. Moore who had days earlier decided to resign from the army rather than fight in the Mexican War. The artillery units were manned by 1st Lieutenants Braxton Bragg, George H. Thomas, Arnold Elzey, John Reynolds and others.
The Mexicans soon crossed the river and surrounded the fort, even as their mortar and cannon fire kept pressure on the American soldiers inside. The Mexicans kept up a steady but ineffective rifle fire that failed to unnerve the Americans who held their ammunition and their ground.
On day three, Wednesday, May 6th, a cannon ball took Major Brown's left leg off. As Brown lay there mortally wounded, Mexican General Ampudia sent a surrender delegation to the fort, but new acting commander Captain Edgar A. Hawkins gathered his fellow officers and by unanimous vote chose to reject the Mexican capitulation demand. The Mexicans then charged the fort from the rear but Lt. Bragg's 6-pounder battery dispersed them with canister shot.
Another day passed under fire while inside the fort the soldiers remained on alert and a tall, angular young civilian laundress named Sarah Borginnis took on the task of tending to the sick and wounded, cooking, and comforting the other civilians. The same day 2nd Lt. Earl Van Dorn of Co K dashed out of the fort and, dodging rolling cannonballs and whizzing bullets, raised a US flag that that had come off its lanyard.
On Friday, May 8th, Taylor and his army arrived back from Point Isabel and the bulk of the Mexican army set out to meet him. Taylor defeated the Mexicans at the Battle of Palo Alto that day and, on May 9th, he defeated them again at the Battle of Resaca del Palma. The Mexicans re-crossed the Rio Grande, fled from Matamoros, and abandoned the six-day Siege of Fort Texas. Major Brown and Sergeant Weigert were the only American deaths and only a handful of soldiers were wounded. The 500 men of Fort Texas had held against a 2,000 man Mexican force and much superior firepower. The fort was immediately renamed Fort Brown in honor of its gallant commander, and the city of Fort Brown later grew up around it. The American army went on to defeat the Mexicans again in late September 1846 at Monterrey, where Captain Gatlin was wounded in the shoulder while leading his company in street-to-street combat. Most of the defenders of Fort Texas took part in that campaign and others until the end of the war in January 1848.
Including the future adversaries in the critical Battle of Chickamauga, Braxton Bragg and George H. Thomas, at least seventeen future Civil War generals were among the Fort Texas defenders, eight for the Union and nine for the Confederacy. The future Union generals were Joseph K. F. Mansfield (killed at Antietam), John F. Reynolds (killed at Gettysburg), George H. Thomas (the Rock of Chickamauga), Samuel B. Hayman, Napoleon J. T. Dana, Henry B. Clitz, Gabriel Paul, and Joseph Potter. The future Confederate generals included: Braxton Bragg, Arnold Elzey, Gabriel Rains, T. H. Holmes, Lewis Henry Little (killed at the Battle of Iuka in Mississippi in 1862), Franklin Gardner, LaFayette McLaws, Earl Van Dorn (murdered by a jealous husband in 1863 in Tennessee), and our own Richard C. Gatlin. In addition, Dixon Miles, as a Union colonel, was mortally wounded by Confederate cannon fire at Harpers Ferry in 1862. Also, Gatlin's good friend and fellow Fort Texas defender Daniel P. Whiting rose to the rank of colonel in the Civil War Union Army. There may not have been another such compact concentration of future Civil War generals in any US Army engagement prior to the Civil War.
Postscript: The six-foot tall heroine of Fort Brown, Sarah Borginnis (or Bowman, her subsequent married name), became a legend in her own right as she continued to serve the US Army for twenty more years. Her nickname was "The Great Western" and following her death in 1866 she was breveted an honorary Army colonel and buried with military honors in the Fort Yuma cemetery.