On May 13, 1846, the United States Congress, egged on President James K. Polk, declared war on Mexico. In 1879, Ulysses S. Grant, who had fought in the war as a strapping young lad, described the whole affair as “wicked” and that the land grab made him “ashamed of [his] country.” Abraham Lincoln was a freshman in the House of Representatives during the war, and he was one of its harshest critics. Alas, Mr. Lincoln was voted in to office after war had already been declared.
It wasn’t just Whigs who opposed the war, either. John C. Calhoun, one of Polk’s fellow Democrats, was relentless in opposing Manifest Destiny. For him, like the Whigs in the North, any territory taken from Mexico would only augment the wound of slavery throughout the republic.
The war itself lasted only two years, from 1846-48, but the consequences were of lasting importance. The United States of America annexed more than half of Mexico’s territory and established itself as the strongman of the region. Here are the five battles that made it all happen:
5. Siege of Veracruz (March 9–29, 1847). Like most of the battles and sieges of the war, this one ended with an American victory. The siege also marked the first official amphibious assault of the U.S. military. Capturing Veracruz was no small feat. At the time, Veracruz was considered the most impenetrable fortress in North America. The victory helped the Americans establish themselves deep in Mexican territory and paved a relatively clear path towards the Mexican capital.
4. Battle of Cerro Gordo (April 18, 1847). The first major battle to result from the American march towards Mexico City, the Battle of Cerro Gordo was massive by the standards of the war -- 12,000 American soldiers attacked 8,700 Mexican soldiers who had dug in deep at a mountain pass called the Cerro Gordo. The Americans took it in one day, but not before slaughtering 1,000 Mexican soldiers. Several famous American men got their chops at the Battle of Cerro Gordo, including Ulysses S. Grant and Robert E. Lee. The battle was so successful that several towns are named after it: one each in Iowa, North Carolina, and Illinois.
3. Siege of Pueblo de Taos (February 3-5, 1847). This was the battle that ended the Taos Revolt, a sidestory of the war that is useful for understanding just how complex the Mexican-American War was. After the American military had taken present-day New Mexico from the Mexicans, the locals revolted against the United States occupation, not necessarily because they were loyal to Mexico (which they were not), but because they thought they deserved more of a voice in how to move forward. The Taos Revolt forced the Americans to think more carefully about occupation and annexation, and earned the citizens of New Mexico a seat at the table in Washington when it came to divvy up the spoils of war.
2. Battle of Molino del Rey (Sept. 8, 1847). Fought on the outskirts of Mexico City, the Battle of Molino del Rey was one of the war’s bloodiest (less than 900 soldiers, added together on both sides, died). The Mexican Army was basically making one last, gallant stand, and it did, but it was no match for the American invaders. The one-day battle allowed the United States military to begin preparing for a siege of Mexico City proper, which fell one week after the Battle of Molino del Rey.
1. Battle of Buena Vista (Feb. 22-23, 1847). In Coahuilla, one Mexico’s northernmost states today (and a good candidate for statehood within the US), just over 15,000 Mexican soldiers were decisively beaten by a much smaller, better-armed American force of just under 5,000 soldiers (who were led by future president Zachary Taylor). The Battle of Buena Vista, while being one of the largest battles of the war, also served as a sign for things to come during the short war. Two hundred and sixty-one Americans died in the battle, and the Mexicans lost 591 soldiers.
Yes, I know most of these battles were fought in 1847, but to be honest that’s pretty much the only year where the two militaries fought seriously. In 1846, both sides were arming and strategizing and traveling, and in 1848 both sides were trying to figure out how to end the lopsided affairs as quickly and as gentlemanly as possible.
Mexico fell further into disrepair after the war, but the United States did not fare much better. Most historians today recognize that the land grab led directly to the Civil War. Calhoun had been correct all along: a successful war against Mexico would only bring slavery to the forefront of American society.