From 1800 to 1848 in the United States, Westward Expansion was a defining theme

Posted: September 20th, 2023

From 1800 to 1848 in the United States, Westward Expansion was a defining theme in American history. Two significant events that impacted this expansion were the Independence of Texas and the Mexican War of 1846-1848.
Independence of Texas: The independence of Texas from Mexico in 1836 profoundly impacted Westward Expansion. American settlers, often called “Texians,” moved into Mexican-controlled Texas in large numbers in the early 1800s. The most significant event was the Texas Revolution (1835-1836), which led to Texas declaring its independence from Mexico(Jenkins, 2017). The impact of this event on Westward Expansion was substantial because it created an independent republic that sought to join the United States(Farmer, 2019). In 1845, Texas was annexed by the U.S. and became the 28th state, further expanding the nation’s territory.
Mexican War of 1846-1848: The Mexican War was another pivotal event in Westward Expansion. The conflict began over a dispute regarding the Texas-Mexico border, with the U.S. claiming the Rio Grande as the border and Mexico insisting it was the Nueces River(Farmer, 2019). This war resulted in significant territorial gains for the United States, including acquiring present-day California, Nevada, Utah, Arizona, New Mexico, and parts of Colorado, Wyoming, Kansas, and Oklahoma through the Treaty of Guadalupe Hidalgo (1848).
Impact Comparison: While both events substantially impacted Westward Expansion, the Mexican War of 1846-1848 is arguably more impactful due to the vast territorial acquisitions it brought about. The war not only expanded the U.S. territory but also laid the foundation for the future development of the American West. The addition of California was of enormous economic and strategic importance due to the California Gold Rush that followed shortly after that.
Manifest Destiny’s Effects: The ideology of Manifest Destiny played a crucial role in both of these historical events:
Independence of Texas: Manifest Destiny, the belief that it was America’s destiny to expand across the continent, played a significant role in the influx of American settlers into Texas. Many saw Texas as a stepping stone towards fulfilling this destiny, and their presence there was driven by the desire to expand American influence(Bozeman, 2014). The annexation of Texas was seen as a step towards manifest destiny by those who believed in the idea.
Mexican War of 1846-1848: Manifest Destiny was a driving force behind the Mexican War. The belief that the United States was destined to stretch from coast to coast fueled the desire to acquire Mexican territory. President James K. Polk, a strong advocate of Manifest Destiny, used the border dispute as a pretext to initiate the war(Jenkins, 2017). The acquisition of vast territories in the Treaty of Guadalupe Hidalgo directly manifested this expansionist ideology.
In both cases, Manifest Destiny provided ideological justification and motivation for territorial expansion. It shaped the mindset of many Americans, influencing their actions and decisions in pursuing westward development during this period.