This Day In History: The Americans Seize the Fortress of Chapultepec in Mexico (1847)

On this day in history, the American army wins the last major battle of the Mexcian-American War. In 1847, General Winfield Scott effectively ends the war by capturing the  Chapultepec fortress on the approaches to Mexican City.

The war between the US and Mexico began after a border dispute. Washington asserted that the Rio Grande was the border between America and Mexico. The government in Mexico City disputed this and threatened force. Texas had become independent shortly before and had become one of the  states of the American Republic.

President James Polk  was determined to force the issue and to demonstrate to Mexico and the world that the Rio Grande was the border. He ordered General Zachary Taylor to advance to the disputed Rio Grande border. The Mexican government was enraged. Texas had been part of Mexico until a revolt by the Texans. They had driven the Mexicans from Texas and had achieved statehood within the United States of America. Mexico did not recognize the State of Texas and they still regarded it as Mexican territory. As a result, they refused to recognize the Rio Grande as the border between the two nations as this would have meant that the were recognizing that Texas was not part of Mexico. The American’s presence near the Rio Grande was seen as an invasion of Mexican soil. The government in Mexico City ordered the Mexican army across the Rio Grande, and it attacked some America units. Within weeks the two nations had formally declared war on each other.

American troops entering Mexico City (1847)

The Mexican army was bigger than the American army, but it was inferior in almost every other way. The leaders were poor and the men were poorly motivated. The firearms of the Mexicans were poor and often malfunctioned. The cannons used by the Mexcian artillery were often of poor quality and were quite ineffective.

By early 1847 General Taylor had conquered California, modern New Mexico and Arizona. The Americans swept the Mexican army from these areas with little difficulty. However, Taylor was reluctant to take the war into the heart of Mexico, he feared getting bogged down in a guerrilla war. The President, who was totally committed to the war instead turned to General Winfield Scott to lead an invasion of the Mexican heartland.  The US invaded Mexico with an amphibious force, that landed in Vera Cruz with some 15,000 men. They bypassed the Mexican defenses and headed straight for Mexico City. The Mexican government was in crisis and the army was left leaderless.  General Scot marched on Mexico City, after some failed peace negotiations. On this day he seized the historic fortress at Chapultepec and  its fall meant that the last significant obstacles to the American advance on Mexico City was removed.  The fortress was taken with relatively little fighting as by this stage the Mexican army was totally demoralized. Mexico City was abandoned by the government and on September 14, Scott marched his army into Mexico City and occupied the Mexican capital.