On Sept. 13, 1847, the American army assaulted the Mexican Military Academy, a fortress known as Chapultepec, which guarded the gates to Mexico City. Although the Mexicans inside fought valiantly, they were outgunned and outnumbered and were soon overrun. With Chapultepec under their control, the Americans were able to storm two of the city gates and by nightfall were in tentative control of Mexico City itself. Although the Americans captured Chapultepec, the battle is a source of great pride for Mexicans today, as young cadets fought bravely to defend the fortress.

Mexico and the United States had gone to war in 1846. Among the causes of this conflict were Mexico's lingering anger over the loss of Texas and the US' desire for Mexico's western lands, such as California, Arizona, and New Mexico. The Americans attacked from the north and from the east while sending a smaller army west to secure those territories they wanted. The eastern attack, under General Winfield Scott, landed on the Mexican coast in March of 1847. Scott made his way towards Mexico City, winning battles at Veracruz, Cerro Gordo, and Contreras. After the Battle of Churubusco on August 20, Scott agreed to an armistice which lasted until Sept. 7.

The Battle of Molino del Rey

After talks stalled and the armistice was broken, Scott decided to hit Mexico City from the west and take the Belén and San Cosme gates into the city. These gates were protected by two strategic points: a fortified old mill named Molino del Rey and the fortress of Chapultepec, which was also Mexico's military academy. On September 8, Scott ordered General William Worth to take the mill. The Battle of Molino del Rey was bloody but short and ended with an American victory. At one point during the battle, after fighting off an American assault, Mexican soldiers crept out of the fortifications to kill American wounded: the Americans would remember this hateful act.

Chapultepec Castle

Scott now turned his attention to Chapultepec. He had to take the fortress in combat: it stood as a symbol of hope for the people of Mexico City, and Scott knew that his enemy would never negotiate a peace until he had defeated it. The castle itself was an imposing stone fortress set on the top of Chapultepec Hill, some 200 feet above the surrounding area. The fortress was relatively lightly defended: about 1,000 troops under the command of General Nicolás Bravo, one of Mexico's better officers. Among the defenders were 200 cadets from the Military Academy who had refused to leave: some of them were as young as 13. Bravo had only about 13 cannons in the fortress, far too few for an effective defense. There was a gentle slope up the hill from Molino del Rey.

Assault of Chapultepec

The Americans shelled the fortress all day on September 12 with their deadly artillery. At dawn on the 13th, Scott sent two different parties to scale the walls and assault the castle: although resistance was stiff, these men managed to fight their way to the base of the walls of the castle itself. After a tense wait for scaling ladders, the Americans were able to scale the walls and take the fort in hand-to-hand fighting. The Americans, still angry over their murdered companions at Molino del Rey, showed no quarter, killing many wounded and surrendering Mexicans. Nearly everyone in the castle was killed or captured: General Bravo was among those taken prisoner. According to legend, six young cadets refused to surrender or retreat, fighting to the end: they have been immortalized as the "Niños Héroes," or "Hero Children" in Mexico. One of them, Juan Escutia, even wrapped himself in the Mexican flag and leaped to his death from the walls, just so that the Americans would not be able to take it in battle. Although modern historians believe the tale of the Hero Children to be embellished, the fact is that the defenders fought valiantly.

Death of the Saint Patricks

A few miles away but in full view of Chapultepec, 30 members of the St. Patrick's Battalion awaited their grim fate. The Battalion was composed mainly of deserters from the US army who had joined the Mexicans: most of them were Irish Catholics who felt that they should be fighting for Catholic Mexico instead of the USA. The Battalion had been crushed at the Battle of Churubusco on August 20: all of its members were dead, captured or scattered in and around Mexico City. Most of those that had been captured were tried and sentenced to death by hanging. 30 of them had been standing with nooses around their necks for hours. As the American flag was raised over Chapultepec, the men were hanged: it was meant to be the last thing they ever saw.

The Gates of Mexico City

With the fortress of Chapultepec in their hands, the Americans immediately attacked the city. Mexico City, once built over lakes, was accessed by a series of bridge-like causeways. The Americans assaulted the Belén and San Cosme causeways as Chapultepec fell. Although resistance was fierce, both causeways were in American hands by the late afternoon. The Americans drove the Mexican forces back into the city: by nightfall, the Americans had gained enough ground to be able to bombard the heart of the city with mortar fire.

Legacy of the Battle of Chapultepec

On the night of the 13th, Mexican General Antonio López de Santa Anna, in overall command of the Mexican forces, retreated from Mexico City with all available soldiers, leaving it in American hands. Santa Anna would make his way to Puebla, where he would unsuccessfully try to sever the American supply lines from the coast.

Scott had been correct: with Chapultepec fallen and Santa Anna gone, Mexico City was well and truly in the hands of the invaders. Negotiations began between the American diplomat Nicholas Trist and what was left of the Mexican government. In February they agreed on the Treaty of Guadalupe Hidalgo, which ended the war and ceded vast tracts of Mexican land to the USA. By May the treaty had been ratified by both nations and was officially implemented.

The Battle of Chapultepec is remembered by the U.S. Marine Corps as one of the first major battles in which the corps saw action. Although the marines had been around for years, Chapultepec was their highest-profile battle to date: the Marines were among those who had successfully stormed the castle. The marines remember the battle in their hymn, which begins with "From the halls of Montezuma…" and in the blood stripe, the red stripe on the trousers of the marine dress uniform, which honors those who fell at the Battle of Chapultepec.

Although their army was defeated by the Americans, the Battle of Chapultepec is a source of much pride for Mexicans. In particular, the "Niños Héroes" who bravely refused to surrender, has been honored with a memorial and statues, and many schools, streets, parks, etc. in Mexico are named for them.