His expansionist appetite whetted by the 1845 annexation of Texas, U.S. president James K. Polk sought war with Mexico to force more territorial concessions.

Thanks to the recently developed electric telegraph network, word of the United States’ first victories against Mexico in Texas at Palo Alto and Resaca de la Palma (May 8–9, 1846) spread like a grassland wildfire. Public meetings convened in towns large and small to validate the young nation’s first expansion by military force. The citizens of Stroudsburg, in eastern Pennsylvania, were typical as they passed resolutions hailing Brigadier General Zachary Taylor as a “man equal to all emergencies,” whose “military skill and undaunted courage…have covered him with fresh laurels and adorned the American arms with unfading glory.” There was praise too for the U.S. Army’s “glorious and triumphant defence of American rights.” Through its valor and sacrifice, the southern border of the United States now stretched to the Rio Grande.

In the immediate aftermath of the two hard-fought battles, the 61-year-old Taylor, a crusty army regular whose perpetual preparedness inspired the nickname “Old Rough and Ready,” secured a narrow zone running along both banks of the river and confronted a new challenge: What next? The answer would thrust the young U.S. Army into a battle unlike any it had encountered; in addition to testing the courage, fortitude, and improvisational skills of its warriors, the battle would bring the nation to a dramatic moment of truth for a policy course called “manifest destiny.” Along the way it would season a cadre of junior officers who, two decades later, would lead another, fratricidal struggle for the country’s future.

The man whose expansionist ambitions and political savvy brought the country to this turning point was its 11th president, James K. Polk, who wholeheartedly sought to fill out the map of the United States with western territories taken by legal claim or negotiation, backed by force if necessary. The economic failure of the Texas Republic and its voluntary annexation to the United States started the war with Mexico over their shared boundary, but Polk aspired to much more. General Taylor and most of the regular U.S. Army entered the new state to enforce American claims to the Rio Grande border by fighting and winning two battles, Palo Alto and Resaca de la Palma [See “A ‘Band of Demons’ Fights for Texas,” Winter 2010]. Those victories did not bring the Mexicans to the bargaining table for the larger settlement Polk was seeking, so Taylor received orders from army chief Winfeld Scott to press “toward the heart of the enemy’s country” to force a deal.

Taylor’s plan was to capture Monterrey, a large commercial and administrative center (population 12,000 to 15,000). To accomplish this, he decided to move his army and supplies 100 miles west up the Rio Grande to Camargo before marching overland another 100 miles southwest to Monterrey. The available river steamers were few, indifferently maintained, and often infested by shipworms—plus it was the rainy season, so the river was roiling across its flood plain, making any passage a hard slog. Camargo’s advantage was its location on a direct road to Monterrey, but otherwise it was badly drained and pestilential; diseases killed many more Americans than had fallen in combat. Author Martin Dugard said that “regimental bands so often played a death march for funerals that Camargo’s mockingbirds learned to mimic the refrain.” Nevertheless, on August 18, 1846, Taylor’s men launched their invasion of Mexico from there.

The Mexican force waiting for them was a mix of units that had already fought the Americans, with others from as far away as Mexico City. They were commanded by Major General Pedro de Ampudia, a Cuban-born Spaniard with a reputation for ruthlessness. After fending of initial orders to abandon Monterrey, Ampudia tried to mount a forward defense by opposing Taylor’s advance at some distance, only to scrap the idea when his subordinates balked at taking their men into an open field fight. He contented himself with dispatching cavalry to harass and delay the U.S. advance, neither of which they accomplished.

Ampudia was more successful in fortifying the town. Monterrey spread for a mile along the north bank of the Santa Catarina River. Its western perimeter was guarded by two fortified steep-sided elevations: Loma de Federación (Federation Hill) on the south bank, and Loma de Independencia (Independence Hill) on the north side. Covering its eastern flank were the strongpoints Fort Teneria (the Tannery) and El Rincón del Diablo (the Devil’s Corner). A thousand yards north of the city rose a huge fortification built on the foundations of an unfinished cathedral. Running 200 yards on a side, it had room for 400 soldiers and 30 guns. The defenders knew it as the Citadel, while its attackers called it the Black Fort.

Less visible but no less deadly were the defenses within the city. Its straight streets were easy to barricade and they were lined with mostly one-story whitewashed houses that were stone strong, fat topped, and loopholed—making each a mini- citadel. Add mutually supporting positions, cannons set to sweep the streets, and Monterrey looks like a picture-perfect setting for an ambush. Ampudia nearly squandered his advantages by ordering the leveling of some outlying works he had thought overly exposed, but he changed his mind as the Americans approached.

Taylor, brevetted major general for his successes thus far, evidently knew his business: A day ahead of his main column marched a road-building detail with escort to smooth the way. He advanced his force in careful stages and made certain to secure his supply line. With wagons hard to find, he relied on pack mules, supervised by soldiers with Mexican handlers known as arrieros. It was a thankless task to keep the obstreperous herd moving on any army timetable, and many a quartermaster was reduced to cursing fits, except a certain Second Lieutenant Ulysses S. Grant. “I am not aware of ever having used a profane expletive in my life,” he wrote, “but I would have the charity to excuse those who may have done so, if they were in charge of a train of Mexican pack mules.”

During the initial stages of their march from Camargo, the Americans found pleasure at Mexican open-air village dances called fandangos. As they approached their target, the parties stopped, and when they asked about that they were told: “Si! Mucho fandango a Monterrey!” A lieutenant and future Civil War general named Abner Doubleday translated it: “They are getting up a dance for you in Monterrey.” A dance of death, perhaps?

General Taylor got his first look at the 250-year-old city at approximately 9 a.m. on September 19. Detachments of U.S. engineers scouted the defenses even as the long army column slowly compressed into an area called Bosque de San Domingo, some three miles northeast of the town. Once assembled, the American army would number 6,220 (roughly half regulars and half volunteers), while Monterrey’s defenders totaled 7,303.

Taylor’s engineers recognized that the western hills dominated Monterrey and capturing them would also cut the town’s main supply route—to Saltillo about 50 miles west. Having left most of his heavy siege cannons behind to make better time, Taylor had no choice but to attack. His prior two battles had been designed as straight-ahead assaults, but this time he decided to send one of his three divisions circling west to cut the Saltillo Road and overrun the hills. With the rest of the army he would demonstrate against the eastern defenses to exploit any weaknesses. He was evidently reasoning that, because Ampudia had not aggressively contested his advance, the Mexicans would remain passive while his exposed flanking column executed its mission.

For the encirclement part of his operation, which Taylor deemed “of essential importance,” he chose the division commanded by Brevet Brigadier General William Jenkins Worth. Taylor deplored Worth’s personal conduct (he had taken leave before the first battles over an issue regarding his rank) but trusted him to prosecute the assignment. Worth’s command, with some 1,650 regulars plus the 1st Texas Mounted Rifles, began their movement at 2 p.m. on September 20 and covered two-thirds of the way to their objective before bivouacking for the night. A cold rain was falling and the men had to sleep uncovered in marching formation. A lieutenant (and prospective general) with the martial moniker of Napoleon Jackson Tecumseh Dana remembered it as the “most cheerless, comfortless, unhappy night I ever spent.” Although Ampudia’s main forces remained hunkered down, his scouts reported the movement and some reinforcements were transferred to the western hills.

When Worth’s men resumed their advance at sunrise on September 21, they soon found their path blocked by an enemy cavalry force of 1,500 backed by 500 infantry. In Worth’s unit, the Mexicans faced some stubborn Texans, smartly deployed U.S. infantry, and two batteries of highly mobile light cannons then dubbed “flying artillery.” Participating in this action were yet two more generals-to-be: Lieutenants James Longstreet and George Gordon Meade. The Mexicans scattered and by 8:15 a.m. Worth’s men had cut the Saltillo Road. “The town is ours,” Worth pridefully—and prematurely—reported to Taylor.

Action also got under way at the eastern side of Monterrey as Taylor mounted what he intended to be diversionary moves to prevent Ampudia massing against Worth. But Taylor’s usually sure handling of troops was sadly absent on this day: Units advanced with ambiguous directions, and reinforcements were dispatched in haphazard fashion, following orders brought by officers such as Lieutenant John Pope—who was to be beaten 16 years hence by Robert E. Lee, Stonewall Jackson, and James Longstreet at Second Bull Run.

The division sent to demonstrate against Fort Teneria launched a head-on assault into the city when the commanding officer, Colonel John Garland, acted according to what he thought Taylor would do rather than what his orders broadly instructed. The soldiers struggled past the direct and flanking fire (the latter from the Citadel) to enter the city itself and a whole new world of hurt: The Americans crammed into the narrow streets where they were shredded by Mexican riflemen lining the roofs and blasted by sandbagged cannons shooting straight down the streets. Even an appearance of some flying artillery commanded by Lieutenant Braxton Bragg (also destined for bigger things) failed when their small rounds literally bounced of the buildings’ strong walls.

Taylor seemed to forget his planned diversion as he committed more and more troops to a feint that had become a serious fight. A follow-up wave of Tennessee and Mississippi volunteers captured Fort Teneria. But the deadly street fighting was repeated at other points in the city, and by 5 p.m. Taylor ordered everyone back, save the Fort Teneria garrison. The aimless combat of the day had cost him nearly 400 casualties, easily twice what his entire expeditionary force had suffered in its previous combat. Fortunately for the fate of the army and Taylor’s reputation, Worth accomplished a good deal more during that same day.

Once astride the Saltillo Road, Worth set his mind to executing Taylor’s instructions “to carry the enemy’s detached works in that quarter.” The more he thought about it, the more sense it made to first tackle the 400-foot-high southern elevation—Federation Hill. It appeared to be less densely defended than Independence Hill, overlapping it and offering a better choice of firing options when the time came to assault the northern highland. As Lieutenant Meade noted, it was “necessary to take [both] these heights before we could advance upon the town.”

Worth compiled a storming party of 300 artillerymen serving as infantry (while retaining their distinctive red-striped pants) and 200 Texas Rangers. The soldiers moved out at noon but had trouble finding a ford across the Santa Catarina River, which so delayed them that Worth sent out a second attack group from the 7th U.S. Infantry. There’s planning and there’s luck: Worth enjoyed some of the latter as the two groups were able to merge to overcome the Mexican battery posted on Federation Hill’s western nose. “We raised a tremendous shot,” recalled Lieutenant Dana, “and up the hill we went with a rush, the Texans ahead like devils.”

Once atop the hill, the red legs found that the Mexicans had neglected to disable their cannons when they abandoned the fort. The Americans soon had a 9-pounder firing at the hill’s eastern redoubt, Fort Soldado, and one of their first shots knocked out the enemy’s gun. Te position was then overrun by a third group dispatched by Worth, placing Federation Hill in American hands. Its capture revealed the critical weakness in Ampudia’s defensive scheme: His strongpoints were isolated and could not be reinforced when under attack.

In one of the last actions of the day, the Tennessee and Mississippi volunteers holding Fort Teneria on the eastern side of the battlefield were relieved by other units. As they marched back to the main line, they were attacked by Mexican lancers and might have been slaughtered piecemeal had not Colonel Jefferson Davis (yes, that same Jefferson Davis) organized a firing line that drove of the attackers.

It had not been a strong performance for the army commander; indeed, historian John S. D. Eisenhower calls this “the worst day of Taylor’s career.” In a letter written at the time, sub ordinate George Meade charitably contrasted the “judgment and energy” of Worth with the “impetuosity and fearless courage” of Taylor. It appears that Taylor had no plan to regain the initiative on his side of the battlefield, but of to the west the man he had entrusted with cracking Monterrey’s defensive shell was about to prove his “worth.”

Hardly had Worth’s men secured Federation Hill than their commander began planning to take Independence Hill. Worth put together an assault force of 500 regulars plus Texas Rangers and had them climbing through the thorny undergrowth toward a little Mexican fort at the western end of the 800-foot Independence Hill at 3 o’clock in the morning on September 22. Tanks to some timely foul weather, the attackers were able to get within a few feet of the fort before they were spotted—too late. Before they could be stopped, they were inside the fort routing the defenders.

The Mexicans retained a strong position on the eastern end of Independence Hill in a fortified post known as Bishop’s Palace. It was fronted by a wide-open killing ground making an infantry charge suicidal. Worth could hit it using cannons he was operating on Federation Hill but he needed more punch, so his artillerymen dismantled a 12-pounder not designed to be easily disassembled, hauled the pieces up steep Independence Hill, and were soon blasting Bishop’s Palace. The Mexican officer in charge defied standing orders to maintain a defensive posture and sallied out to attack. That open ground in front of the fort worked both ways as the U.S. riflemen and their one cannon tore bloody rents in the enemy columns; the survivors fed with the Americans pursuing so rapidly that they entered the palace concurrent with the Mexican soldiers. The U.S. fag was flying over it by 4 p.m.

On this second day of the battle, on the eastern side of Monterrey, Taylor did little but tidy up his formations. But there was one dramatic move left: During the night of September 22, Ampudia decided to abandon his outer defenses save for the Citadel and concentrate his men in the town center, the Plaza Mayor. He may have been opting for a battle of attrition, counting on his street defenses to bleed the enemy dry, as they had handily done on September 21. His soldiers holding the eastern side, however, thought otherwise. According to one Mexican account, the “grumbling and discontent showed…openly, and the military morale suffering by it in a manner beyond description.”

One of the first Americans to realize what Ampudia had done was Lieutenant George Meade, sent to investigate a report from an Independence Hill outpost early on September 23 that the city streets appeared deserted. According to Meade, he “ascertained the enemy had abandoned all that portion of the town in our direction, and had retired to the vicinity of the central plaza of the town, where they were barricaded, and all the houses occupied by infantry.” On the eastern side of town, the Americans holding Fort Teneria first noted that their immediate front had been cleared and notified Taylor, who set up his command post there.

The first Americans to enter the city from the east repeated the errors of those who had attacked the northern sector two days before: “Onward we went, men and horses falling at every step,” recalled one of them. “Cheers, shrieks, groans, and words of command added to the din.” There were even a few women among the defenders, who “gave them courage and passed them munitions.” But this time among the American attackers there were Texans who, reports historian Eisenhower, “had been fighting in cities for a decade.” Word spread that there was a better way to defeat the enemy’s defenses: First, capture a house at the end of a block or one with an adjacent empty house. Ten, with riflemen covering them, men with picks and crowbars dig holes in the softer common walls. After the riflemen kill any enemy near the hole, they roll a couple of 6-pound shells with short fuses sputtering into the room to scour remaining defenders. The attackers then rush in, with some mounting the roof to establish a base of fire, while others begin the house-to-house process again. Bragg’s flying artillerymen quickly learned how to load behind a corner, rush the gun out to fire, and then yank it out of sight to reload. We “had to fight them by inches,” Lieutenant Dana said.

Helping keep Worth’s advance on track was Captain John Pemberton, who, 16 years later would surrender Vicksburg. Taylor and Worth had yet to coordinate their efforts, though the army commander had sent his subordinate a 10-inch mortar, which, once posted in a cemetery, began lobbing shells into the Plaza Mayor. This heavy artillery convinced General Ampudia that the battle was lost. He had turned the cathedral in the square into an ammo dump and could imagine the devastation should one of those mortar rounds hit his explosives.

From Taylor’s perspective, the house-to-house fighting on the eastern side only constituted a reconnaissance, so he saw nothing wrong in terminating the fighting at 2 p.m. preparatory to mounting an all-out attack the next day. Worth halted his advance when he heard the firing die out in the east—though he kept that mortar active. Neither evidently realized that the battle had been won.

Ampudia sent a message at 3 a.m., September 24, proposing negotiations for capitulation. A back-and-forth exchange ensued, with meetings between the commanders. The terms that were signed early on September 25 surrendered the town, all weapons (personal guns exempted), and public property. In return Ampudia’s men (permitted to take along a six-gun field battery) were to march out west on the Saltillo Road. A truce was put in place for eight weeks—less if their respective governments deemed it.

The closer one was to the fighting, the more sensible Taylor’s terms seemed. While not a Pyrrhic victory, it came awfully close: Monterrey had been an unexpectedly tough nut to crack. “The place is a second West Point in strength,” wrote Lieutenant Dana, “and the Mexicans have defended it to the last… our fighting has been bloody and hard.” Taylor’s losses of 120 killed, 368 wounded, and 43 missing represented 8.5 percent of his force, while Ampudia’s total casualties of 367 were just 5 percent of his. There were increasing discipline problems with the American volunteer elements, and the dependable regulars were frazzled by constant hard duties.

All the way back in Washington those impressions were reversed: President Polk felt that Taylor had wasted his victory by not paroling Ampudia’s army but had to mute his criticism in the face of great public accolades over Taylor’s accomplishment. Still, he was right that the U.S. capture of Monterrey did not end the Mexican-American war. Nor did it provide a gateway to Mexico City, since the American supply system could not stretch the thousand land miles required. The most Polk could do to show his displeasure was to abbreviate the eight-week truce.

Taylor faced an extended period overseeing the American occupation of the region, followed by a final northern battle when the reconstituted Mexican army—led by Antonio López de Santa Anna and including the Monterrey garrison—fought and lost at Buena Vista in February 1847. Forcing the Mexican government to the bargaining table and obtaining the territorial concessions that would realize Polk’s vision of a continental United States required an invasion from the sea and a long march into Mexico’s capital. Nevertheless, the Monterrey engagement lingered long in the memories of the men who fought there. One veteran division commander afterward declared, “I do not believe that for downright, straightforward, hard fighting, the battle of Monterey has ever been surpassed.”


Noah Andre Trudeau is a media producer and writer. He is currently finishing work on a book about Abraham Lincoln’s visit to the war front in March–April 1865 and developing a concert work for narrator, orchestra, and video about Lincoln’s life.

Originally published in the April 2014 issue of Military History Quarterly. To subscribe, click here.