The Mexican American war broke out in 1846 under the new president, James K Polk. Polk saw it as his duty to spread democracy throughout the world. His first mission was to make Texas part of U.S. territory. Mexico was not happy, perceiving this annexation as an act of war. For the most part, prior to this at Alamo, the US government did not intervene for Texans. But now, ten years later the Mexican president, Antonio López de Santa Anna was unpopular. Mexicans were not happy, the government was unstable and the army was weak with famine and disease.
The war lasted for one year and nine months, as many as 25,000 Mexicans died in battle, and Winfield Scott and Zachary Taylor led the American army to victory. Their troops made substantial acquisitions of land, but the predicament of slavery would eventually lead to unrest within the United States itself.
The Fight for Texas
Mexico won independence from Spain in 1821 when Texas was still part of the country. Settlers from America and around the world flocked to Texas, and they began to dispute choices made by the Mexican ruling classes. In 1836, the Texas Revolution led to independence. But Mexico did not recognize the Republic of Texas as a separate nation. Texas asked to become the 28th state in America, and America annexed it in 1845.
Mexican American War: The Beginning
The United States offers to buy Texas and the land extending to the Pacific Ocean. Diplomacy was not strong on the U.S. side as Mexico felt insulted by the offer. An argument broke out about where the border in Texas was. Mexico claiming it was at the Nueces River, and the United States stating it was further south near the Rio Grande River. Polk sent troops down to protect their border, and on April 25th, 1846, Mexican soldiers crossed the Rio Grande and launched an attack on the Americans.
Congress approved Polk’s declaration of war on May 13th, 1846 and Taylor led his troops towards Mexico. Taylor’s forces’ first encounter was at the battle of Palo Alto, where they forced the Mexican soldiers into retreat. Taylor advanced into Mexico and fought the battles of Monterrey and Buena Vista. Taylor won at Buena Vista despite having only 5,000 men to Mexicos 14,000.
Mexico In Divide
Polk saw Taylor as a rival, and instead of reinforcing his army so they could capture Mexico City, he sent in a second army led by Scott. America gained control of the Mexican capital, and the two countries agreed to a peace pact called the Treaty of Guadalupe Hidalgo. The treaty outlined the contract between Mexico and the U.S., wherein America paid $15 million for Mexico to give up its claim to Texas. Additionally, it handed over the land that would become southwestern Wyoming, southwestern Colorado, Utah, Nevada, New Mexico, Arizona, and California. As a result, Mexico has 32 states, just 45% of its original territory.
Slavery and the American Civil War
While the incredible gains made by America were a victory, it also led to conflict over whether slavery would be legal in these newly formed territories. These arguments would eventually lead to the outbreak of the American Civil War in 1861.
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