Mexican War (1846-1848) – is a war between the U.S. and Mexico, which resulted in capturing by the US of more than half of the Mexican territory, accounting for nearly a one third of the present territory of the United States.
The prerequisites for the conflict were the following. In 1835, the American plantation owners who had settled in Mexican Texas a couple of years earlier, made with the support of the U.S. ruling circles a rebellion, in 1836 declared a secession of Texas from Mexico and proclaimed it an independent state. It needs to be mentioned “Texas was the first region of northern Mexico to be settled by significant numbers of Americans. The Mexican government, hoping to develop the area, accepted an offer by Moses Austin to colonize the area with Americans” (Foner 1).
With the help of the army commanded by Sam Houston, which routed Santa Ana's army, Texan independence was recognized. Newly elected President James K. Polk (1845-1849) had four main goals for his presidency: to reduce the tariff, to reestablish the Independent Treasury, to settle the Oregon dispute, and to bring California into the United States (Foner 2). However, Mexico was refusing any negotiations on selling California. Hence, Polk was forced to declare war.
In February 1845 Texas was annexed by the United States, despite the fact that the Mexican government in 1843 had warned that it would consider the annexation as a declaration of war against Mexico.
The direct cause of the war was the dispute over the southern border of Texas. Mexico stated that the Nueces River divides two countries, while the Americans claimed that the border line is at Rio Grande that is dozens of miles to the South. Meeting in Mexico went unspoken American mission of John Slidell (1793 – 1871), who was also tasked to solve the issue of acquisition of California and New Mexico for $25 million. However, the Mexican dictator Antonio Santa Ana (1794-1876) refused Slidell`s offer.
In January 1846, U.S. President James K. Polk ordered troops under the command of Zachary Taylor (1784-1859, President of the USA in 1849-1850) to occupy the disputed land on the southern border of Texas and to reach the shore of Rio Grande, where the first encounter with Mexican troops took place.
After an attempt of the Mexicans to force Taylor squads out of Nueces River, on May 13, 1846 Congress declared war against Mexico. Despite the superiority of American troops, the Mexicans showed severe resistance, and in areas captured by invaders guerrilla war broke out.
U.S. troops occupied in 1846 and early 1847 a significant portion of California and Northern Mexico. Having received the order to invade the central regions of Mexico, Taylor captured Monterrey and in February 1847 defeated a large army of the Mexicans under the command of Santa Anna at the Battle of Buena Vista where the latter suffered more than 3,500 casualties. In March 1847, American military units under the command of General Winfield Scott crossed the Gulf of Mexico and landed in Veracruz.
Scott performed the first in the U.S. history major amphibious landing in preparation for the siege of Veracruz. More than 12 thousand American soldiers besieged Veracruz and conducted massive barrages of the city. Mexican army morale soon vanished and the city was surrendered in 12 days after the beginning of the siege. The Americans lost 13 people killed and 55 wounded, while the Mexicans – about 180 of killed and wounded, more than half of whom were civilians.
Having captured the port city on March 27, 1847, the Americans launched an offensive against Mexico. After defeating the Mexicans at Cerro Gordo and Contreras, Scott entered Mexico City on September 14 the same year.
Despite the loss of the capital city and other towns, the Mexicans continued to fight against invaders resorting to guerrilla methods, however, the ruling circles decided to conclude peace.
On February 2, 1848 the Guadalupe - Hidalgo Treaty was signed, under which Mexico lost more than half of its territory – almost the entire territory of the modern states of New Mexico, Utah, Nevada, Arizona, California, Texas and Colorado for a remuneration of $ 15 million (Foner 2). Moreover, the treaty above mentioned “guaranteed male citizens their liberty, property, and all the rights of American citizens, while regarding Indians only as “savage tribes” (Foner 3). Mexico was forced into a draconian peace when the capital was occupied Mexican armies were smashed and Mexican resistance was broken. It needs to be noticed, in this war, future U.S. president Zachary Taylor won glory for his successful and well-elaborated military campaigns. Joining the vast territories in the south again exacerbated the issue over borders of extension of slavery in the United States. While slavery in Mexico was abolished, in Texas it was accepted on the constitutional level. Civil rights to Indians and blacks were denied, and only whites were able to fully exercise their human rights. Moreover, Texas became a state only in 1912 when “too Mexican” population was assimilated with whites (Foner 3).
Foner Eric. Give Me Liberty!: An American History. Chapter 13: A House Divided, 1840–1861 [Sample Lecture].