Final Victory: Battle of Chapultepec

On September 12, 1847, during the Mexican-American War the Battle of Chapultepec began. From the article:

"The Assault
At dawn on September 12, American artillery began firing on the castle. Firing through the day, it halted at nightfall only to resume the next morning. At 8:00 AM, Scott ordered the firing to stop and directed the attack to move forward. Advancing east from Molino del Rey, Major General Gideon Pillow's division pushed up the slope spearheaded by an advance party led by Captain Samuel Mackenzie. Advancing north from Tacubaya, Major General John Quitman's division moved against Chapultepec with Captain Silas Casey leading the advance party.

Pushing up the slope, Pillow's advance successfully reached the walls of the castle but soon stalled as Mackenzie's men had to wait for the storming ladders to be brought forward. To the southeast, Quitman's division encountered a dug-in Mexican brigade at the intersection with the road leading east into the city. Ordering Major General Persifor Smith to swing his brigade east around the Mexican line, he directed Brigadier General James Shields to take his brigade northwest against Chapultepec. Reaching the base of the walls, Casey's men also had to wait for ladders to arrive.

Ladders soon arrived on both fronts in large numbers allowing the Americans to storm over the walls and into the castle. The first over the top was Lieutenant George Pickett. Though his men mounted a spirited defense, Bravo was soon overwhelmed as the enemy attacked both fronts. Pressing the assault, Shields was severely wounded, but his men succeeded in pulling down the Mexican flag and replacing it with the American flag. Seeing little choice, Bravo ordered his men to retreat back to the city but was captured before he could join them.

Exploiting the Success
Arriving on the scene, Scott moved to exploit the capture of Chapultepec. Ordering Major General William Worth's division forward, Scott directed it and elements of Pillow's division to move north along the La Verónica Causeway then east to assault the San Cosmé Gate. As these men moved out, Quitman re-formed his command and was tasked with moving east down the Belén Causeway to conduct a secondary attack against the Belén Gate. Pursuing the retreating Chapultepec garrison, Quitman's men soon encountered Mexican defenders under General Andrés Terrés.

Using a stone aqueduct for cover, Quitman's men slowly drove the Mexicans back to the Belén Gate. Under heavy pressure, the Mexicans began to flee and Quitman's men breached the gate around 1:20 PM. Guided by Lee, Worth's men did not reach the intersection of the La Verónica and San Cosmé Causeways until 4:00 PM. Beating back a counterattack by Mexican cavalry, they pushed towards the San Cosmé Gate but took heavy losses from the Mexican defenders. Fighting up the causeway, American troops knocked holes in the walls between buildings to advance while avoiding Mexican fire.

To cover the advance, Lieutenant Ulysses S. Grant hoisted a howitzer to the bell tower of the San Cosmé church and began firing on the Mexicans. This approach was repeated to the north by US Navy Lieutenant Raphael Semmes. The tide turned when Captain George Terrett and a group of US Marines were able to attack the Mexican defenders from the rear. Pushing forward, Worth secured the gate around 6:00 PM.

Aftermath
In the course of the fighting at the Battle of Chapultepec, Scott suffered around 860 casualties while Mexican losses are estimated at around 1,800 with an additional 823 captured. With the city's defenses breached, Mexican commander General Antonio López de Santa Anna elected to abandon the capital that night. The following morning, American forces entered the city. Though Santa Anna conducted a failed siege of Puebla shortly thereafter, large-scale fighting effectively ended with Mexico City's fall. Entering into negotiations, the conflict was ended by the Treaty of Guadalupe Hidalgo in early 1848. The active participation in the fighting by the US Marine Corps led to the opening line of the Marines' Hymn, "From the Halls of Montezuma...""