Battle of Monterrey

September 21–24, 1846 — Mexican-American War

The Battle of Monterrey was fought from September 21–24, 1846, between the United States and Mexico, during the Mexican-American War. The outcome of the battle was an American victory and helped the U.S. gain control of Northern Mexico.

Battle of Monterrey, Storming Independence Hill, LOC

This illustration depicts American forces storming Independence Hill during the Battle of Monterrey. Image Source: Library of Congress.

Battle of Monterrey Facts

  • Date — September 21–24, 1846.
  • Location — Monterrey, Nuevo León, Mexico.
  • Belligerents — United States of America and Mexico.
  • American CommanderZachary Taylor.
  • Mexican Commander — Pedro de Ampudia.
  • Winner — The United States won the Battle of Monterrey.

Battle of Monterrey Significance

The Battle of Monterrey was important to the outcome of the Mexican-American War because American forces gained control of Northern Mexico. General Zachary Taylor’s victory also set the stage for the Battle of Buena Vista (February 22–23, 1847) and the Mexico City Campaign, which was led by General Winfield Scott.

Battle of Monterrey, Americans Advance on the Main Plaza
This illustration depicts Americans forcing their way to the Main Plaza in Monterrey on September 23, 1846. Image Source: Yale University Library.

Battle of Monterrey History

The Battle of Monterrey was one of the most important battles that took place during the Mexican-American War. After winning the Battle of Palo Alto (May 8, 1846) and the Battle of Resaca de la Palma (May 9, 1846), U.S. General Zachary Taylor captured the Mexican city of Matamoros, south of the Rio Grande River. Taylor occupied the city, and the strength of his army was around 14,500 men. 

U.S. Forces Move Up the Rio Grande

On July 6, Taylor started moving up the Rio Grande, taking about half of his troops. By July 14, he arrived at Camargo on the San Juan River, a tributary of the Rio Grande, and set up a supply base.


Meanwhile, General Mariano Arista, leading the Mexican Army of the North, anticipated Taylor’s target was Monterrey, Mexico, nearly 200 miles from Camargo.  

Monterrey was a relatively small city, with around 10,000 residents. Situated on the southern bank of the Santa Catarina River, it measured approximately one mile in length and half a mile in width. The city featured narrow streets that could be easily blocked off, and many of its buildings were flat-roofed and constructed from stone, making them ideal for defensive purposes.

Battle of Monterrey, 1846, American Forces Advance, LOC
This illustration depicts American forces fighting in Monterrey. Image Source: Library of Congress.

Mexican Defenses at Monterrey

To prepare the city, Arista sent a battalion of engineers and sappers — construction workers — to fortify the city. 

Upon their arrival, they strategically placed artillery and strengthened defensive positions. 

North of Monterrey, they fortified an unfinished cathedral, which later became known as La Ciudadela — Citadel. 

To the East, they secured La Teneria, a stone tannery, and established a fort called El Rincón del Diablo — Devil’s Corner. 

West of the city, artillery was placed on the hills along the road to Saltillo, southwest of Monterrey. The northern hill was called Loma Independencia — Independence Hill, while the southern one was called Loma Federación — Federation Hill. 

The lower part of Independence Hill was protected by an abandoned building called Obispado — Bishop’s Palace. On Federation Hill was another fortification known as El Soldado. These positions were individually strong but too far from each other to provide mutual support.

The road to Saltillo was important because if the Americans broke through Monterrey, they could march south to Mexico City. They would also block Mexican reinforcements marching north from reaching Monterrey.

Battle of Monterrey, 1846, Bishop's Palace, LOC
This illustration depicts the Bishop’s Palace. Image Source: Library of Congress.

Ampudia takes Command

While the construction of defensive works was going on, General Pedro Ampudia arrived in Monterrey. Mexican President Mariano Paredes y Arrillaga sent Ampudia to take control of Mexican forces because he was upset with Arista’s defeats at Palo Alto and Resaca de la Palma.

Ampudia had a force of roughly 7,000 men, consisting of 4,000 regular soldiers and 3,000 militia, along with 42 cannons.

Taylor Prepares to Attack

By early August, General Taylor had nearly 15,000 men at the camp at Camargo. As many as one-third of them were sick, so Taylor was anxious to leave the camp and march on Monterrey

On August 10, Taylor sent Captain Benjamin McCulloch of the Texas Rangers to scout the roads to Monterrey. Nine days later, on August 19, Taylor led a column of 6,640 troops, out of Camargo, marching toward Monterrey.

Taylor’s forces reached Bosque de San Domingo, also known as Walnut Springs, about three miles from Monterrey, on September 19. 

American Strategy

Taylor’s strategy involved sending 2,000 men under Brigadier General William J. Worth to attack Monterrey from the west. This would cut off the road to Saltillo, preventing Mexican reinforcements from reaching Monterrey, and capture the fortified heights of Federation Hill and Independence Hill. While Worth attacked from the west, Taylor planned to attack Mexican forces to the east, which would distract them from the main attack.

The night of September 20 was cold and rainy. Worth’s force marched into position and camped west of Monterrey. Mexican forces were aware of the move but did very little to counter it.

President Zachary Taylor, Official Portrait, 1849, Bush
General Zachary Taylor. Image Source: White House Historical Society.

The Battle of Monterrey Begins — September 21

The battle started on the morning of September 21 when the Mexican Cavalry, led by Lieutenant Colonel Juan Nájera, attacked the Texas Cavalry commanded by Colonel John Coffee Hayes. The Mexicans, who were using lances, were pushed back twice by heavy artillery fire. They withdrew after suffering approximately 100 casualties, including Lieutenant Colonel Juan Nájera, who was killed.

Meanwhile, Worth’s troops moved forward and successfully blocked the Saltillo Road. Despite intense Mexican gunfire, Captain Charles E. Smith led a group of regular soldiers and Texans in an assault on the west side of Federation Hill. They managed to capture the artillery positions on the hill and used the captured guns to target the Mexican defenses on Independence Hill.

On the east side of Monterrey, Taylor launched his diversionary attack, but it turned into a full-scale attack. However, Taylor made a mistake and failed to provide artillery support for his men.

The first contingent Taylor sent in was from the command of Brigadier General David E. Twiggs. However, they were pinned down by heavy fire from the Mexicans. Twigg was not with his men, because he was sick.

Taylor ordered the division commanded by Major General William O. Butler to reinforce the first contingent. Together, they captured La Tenería and moved toward Monterrey. As the Americans fought their way into the city, they came under heavy fire from Mexican troops on rooftops and in buildings in the narrow streets. 

Taylor decided to withdraw his forces, leaving the Mexicans in control of the strategically important Tenería. 

Once again, American forces spent the night in cold weather while heavy rains fell.

September 22

Taylor held his position on the east side of the city. However, the battle resumed on the west side, where Worth engaged Ampudia early in the morning.

Around 2:00 a.m., Worth ordered his men to advance. An hour later, Lieutenant Colonel Thomas Childs led a contingent of 500 regulars and Texans up the slope of Independence Hill. At the top of the hill, they attacked the hill was the redoubt, El Solado. After intense hand-to-hand combat, the Americans forced the Mexicans to withdraw and raised the American flag over Independence Hill.

Mexican forces launched an unsuccessful counterattack on the top of the hill in the afternoon.

The Americans moved a 12-pounder howitzer to the top of Independence Hill and used it to bombard the Mexican positions near the bottom of the hill, at the Bishop’s Palace. Eventually, the Americans drove the Mexicans away. The Americans took command of the artillery and turned the guns on the Mexicans as they fled.

That night, Ampudia repositioned his forces, withdrawing from most of the outer defenses and concentrating them in Monterrey’s Grand Plaza and the Ciudadela.

September 23

On the morning of September 23, Taylor’s troops took control of the abandoned Mexican outposts on the east side of Monterrey, including El Rincón del Diablo. However, later that afternoon, Taylor ordered his men to withdraw to the outskirts of Monterrey. 

Meanwhile, on the west side, Worth’s forces advanced on the city. They used grape and canister fire from their cannons to clear the narrow streets, advancing methodically block by block, house by house, and room by room, as they moved toward the city plaza.

Leading the way in the fierce fighting were the Texas Rangers. By mid-afternoon, the American forces had nearly reached the heart of the city. 

Taylor declined a request from the Governor of Nuevo León, Don Manuel Maria de Llano for a truce to allow the evacuation of women and children. That night, Worth’s artillery bombarded the city center.

Battle of Monterrey, 1846, Mexican Defenses in the Streets
This illustration depicts the fighting in the streets of Monterrey on September 23. Image Source: Yale University Library.

September 24

By 3:00 a.m. on September 24, Ampudia was concerned the American artillery fire might ignite the substantial stockpile of ammunition stored at the cathedral. He sent a message to Taylor, requesting the “honors of war,” which would allow his men to depart with their flags flying and all their arms and equipment intact. 

Negotiations and Armistice

At first, Taylor declined the request initially but later agreed to meet with Ampudia in the afternoon. By then, the Americans were running low on supplies and ammunition, and they still faced determined Mexicans who were entrenched in the city. 

Taylor agreed to the formation of a commission, with three members from each side to negotiate the terms of capitulation. The commission was able to reach an agreement that satisfied both sides.

  • Ampudia would surrender Monterrey along with its weapons and munitions. 
  • Mexican troops would be permitted to withdraw with their firearms and a single artillery battery consisting of six guns, along with its ammunition. 
  • The Citadel would be immediately surrendered.
  • The evacuation of Monterrey would take place within a week. 
  • Mexican forces would retreat to a position roughly 40 miles beyond the city.

Both sides also committed not to advance beyond this agreed-upon line for eight weeks or until one of the governments formally disavowed the armistice.

Battle of Monterrey, 1846, Mexican Surrender, LOC
This illustration depicts Taylor and Ampudia discussing the capitulation of Monterrey. Image Source: Library of Congress.

American Flag Raised Over Monterrey

On September 25, the Mexican flag was lowered to a 21-gun salute, and in its place, the American flag was raised, accompanied by a 28-gun American salute. U.S. troops marched triumphantly into the city center, to the familiar tune of “Yankee Doodle.”

Estimated Casualties

The Battle of Monterrey resulted in estimated Mexican casualties totaling 430 killed or wounded, while the Americans suffered an estimated 120 killed, 368 wounded, and 43 soldiers reported as missing.

Occupation of Monterrey

Taylor’s acceptance of the armistice was controversial in Washington where the terms were viewed as too generous to the Mexicans. President James K. Polk, in particular, was critical of the decision. However, the armistice likely prevented further U.S. casualties that would have occurred if Taylor had needed to secure the city by force.

Taylor had two reasons for agreeing to the armistice:

  1. He believed that American generosity could expedite the conclusion of the war, particularly because of recent changes in the Mexican Government. 
  2. It allowed him to rest his army and resupply it for the next six weeks, with General Worth governing Monterrey.

President Polk also had concerns about Taylor’s growing popularity, fearing that he might become a candidate for the Whig Party nomination for president in 1848. In response, Polk ordered a large portion of Taylor’s forces to join Major General Winfield Scott and his forces. Scott was planning an invasion of Central Mexico, which he was preparing at Veracruz.

Citation Information

The following information is provided for citations, including APA Style, Chicago Style, and MLA Style.

  • Article Title Battle of Monterrey
  • Date September 21–24, 1846
  • Author
  • Keywords Battle of Monterrey, Mexican-American War, Zachary Taylor, Benjamin McCulloch, William J. Worth, Coffee Hayes, William O. Butler, Texas Rangers
  • Website Name American History Central
  • Access Date May 22, 2024
  • Publisher R.Squared Communications, LLC
  • Original Published Date
  • Date of Last Update October 30, 2023