Battle of Contreras - Conflict & Dates:
The Battle of Contreras was fought August 19-20, 1847, during the Mexican-American War (1846-1848).
Armies & Commanders
Battle of Contreras - Background:
Though Major General Zachary Taylor had triumphed in a series of victories at Palo Alto, Resaca de la Palma, and Monterrey, President James K. Polk decided to shift the focus of the American war effort from northern Mexico to a campaign against Mexico City. Though this was largely due to Polk's concerns about Taylor's political ambitions, it was also supported by intelligence reports that an advance against Mexico City from the north would be exceptionally difficult. As a result, a new army was formed under Major General Winfield Scott and instructed to capture the key port city of Veracruz. Coming ashore on March 9, 1847, Scott's command moved against the city and captured it after a twenty-day siege. Constructing a major base at Veracruz, Scott began making plans to advance inland before yellow fever season arrived.
Moving inland, Scott routed the Mexicans, led by General Antonio López de Santa Anna, at Cerro Gordo the following month. Pressing on, Scott captured Puebla where he paused to rest and reorganize through June and July. Resuming the campaign in early August, Scott elected to approach Mexico City from the south rather than force the enemy defenses at El Peñón. Rounding Lakes Chalco and Xochimilco his men arrived at San Augustin on August 18. Having anticipated an American advance from the east, Santa Anna began redeploying his army to the south and assumed a line along the Churubusco River (Map).
Battle of Contreras - Scouting the Area:
To defend this new position, Santa Anna placed troops under General Francisco Perez at Coyoacan with forces led by General Nicholas Bravo to the east at Churubusco. On the west end of the Mexican line was General Gabriel Valencia's Army of the North at San Angel. Having established his new position, Santa Anna was separated from Scott by a vast lava field known as the Pedregal. On August 18 Scott ordered Major General William J. Worth to take his division along the direct road to Mexico City. Moving along the east edge of the Pedregal, this force came under heavy fire at San Antonio, just south of Churubusco. Unable to flank the Mexicans due to the Pedregal to the west and water to the east, Worth elected to halt.
As Scott pondered his next move, Valencia, a political rival of Santa Anna's, elected to abandon San Angel and moved five miles south to a hill near the villages of Contreras and Padierna. Santa Anna's orders for him to return to San Angel were refused and Valencia argued he was in a better position to defend or attack depending on the enemy's course of action. Unwilling to mount a costly frontal assault on San Antonio, Scott began contemplating moving up the west side of the Pedregal. To scout the route, he dispatched Robert E. Lee, recently brevetted to major for his actions at Cerro Gordo, along with an infantry regiment and some dragoons west. Pressing into the Pedregal, Lee reached Mount Zacatepec where his men dispersed a group of Mexican guerrillas.
Battle of Contreras - Americans on the Move:
From the mountain, Lee was confident that the Pedregal could be crossed. Relating this to Scott, he convinced his commander to change the army's line of advance. The next morning, troops from Major General David Twiggs and Major General Gideon Pillow's division moved out and began constructing a path along the route traced by Lee. In doing so, they were unaware of Valencia's presence at Contreras. By early afternoon, they had reached a point past the mountain to where they could see Contreras, Padierna, and San Geronimo. Moving down the forward slope of the mountain, Twiggs' men came under fire from Valencia's artillery. Countering this, Twiggs advanced his own guns and returned fire. Taking overall command, Pillow directed Colonel Bennett Riley to take his brigade to the north and west. After crossing a small river they were to take San Geronimo and cut off the enemy's line of retreat.
Moving over rough terrain, Riley found no opposition and occupied the village. Valencia, engaged in the artillery duel, failed to see the American column. Concerned that Riley was isolated, Pillow later directed Brigadier General George Cadwalader's brigade and Colonel George Morgan's 15th Infantry to join him. As the afternoon progressed, Riley scouted the rear of Valencia's position. During this time, they also detected a large Mexican force moving south from San Angel. This was Santa Anna leading reinforcements forward. Seeing the plight of his comrades across the stream, Brigadier General Persifor Smith, whose brigade was supporting the guns that were firing on Valencia, began to fear for the safety of the American forces. Unwilling to directly assault Valencia's position, Smith moved his men into the Pedregal and followed the route used earlier. Joining with the 15th Infantry shortly before sunset, Smith began planning an attack on the Mexican rear. This was ultimately called off due to darkness.
Battle of Contreras - A Quick Victory:
To the north, Santa Anna, faced with a difficult road and a setting sun, elected to withdraw back to San Angel. This removed the threat to the Americans around San Geronimo. Consolidating the American forces, Smith spent the evening designing a dawn attack intended to strike the enemy from three sides. Desiring permission from Scott, Smith accepted Lee's offer to cross the Pedregal in the darkness to take a message to their commander. Upon meeting Lee, Scott was pleased with the situation and directed him to find troops to support Smith's effort. Locating Brigadier General Franklin Pierce's brigade (temporarily led by Colonel T.B. Ransom), it was ordered to demonstrate in front of Valencia's lines at dawn.
During the night, Smith ordered his men as well as Riley's and Cadwalader's to form for battle. Morgan was directed to cover the road north to San Angel while Brigadier General James Shields' recently arrived brigade was to hold San Geronimo. In the Mexican camp, Valencia's men were cold and tired having endured a long night. They were also increasingly concerned about the whereabouts of Santa Anna. At daybreak, Smith ordered the Americans to attack. Storming forward, they routed Valencia's command in a fight that lasted only seventeen minutes. Many of the Mexicans attempted to flee north but were intercepted by Shields' men. Rather than come to their assistance, Santa Anna continued falling back towards Churubusco.
Battle of Contreras - Aftermath:
The fighting at the Battle of Contreras cost Scott around 300 killed and wounded while Mexican losses numbered approximately 700 killed, 1,224 wounded, and 843 captured. Recognizing that the victory had unhinged the Mexican defenses in the area, Scott issued a flurry of orders following Valencia's defeat. Among these were orders which countermanded earlier directives for Worth's and Major General John Quitman's divisions to move west. Instead, these were ordered north towards San Antonio. Sending troops west into the Pedregal, Worth quickly outflanked the Mexican position and sent them reeling north. As the day progressed, American forces drove forward on both sides of the Pedregal in pursuit of the enemy. They would catch up with Santa Anna around noon at the Battle of Churubusco.