Title: Westward Expansion (1807-1912): The Mexican War and Political Aftermath | SparkNotes
Headings: Westward Expansion (1807-1912)
Westward Expansion (1807-1912)
The Mexican War and Political Aftermath
Summary
Commentary

Content: The Mexican War lasted one and a half years, and ranged all throughout Texas, New Mexico, and California, and even into the Mexican interior. Mexican resistance was stubborn and benefited from greater manpower than US forces, but ultimately proved futile. The US won an easy victory due to superior artillery and leadership. The Treaty of Guadalupe Hidalgo, signed February 2, 1848, ceded Texas, New Mexico, and California to the US, completing American claims to land all the way across the continent. In return, the US assumed all monetary claims of US citizens against the Mexican government and paid Mexico $15 million. The West was now officially open and secure to Americans. Despite patriotism engendered by the war, sectional conflict grew more dramatic between 1846 and 1848. Not all of this was due to expansion. Polk created many enemies in the North through his lack of support for tariffs and in the West for his failure to initiate internal improvement. However, expansion and the future of slavery generated far greater conflict during the pre-Civil War era.