1. The mexican-american war, 1846 - 1848
From Origins to Consequences…

2. Opponents of the Annexation of Texas
Mexico:
The most outspoken opponent of the annexation of Texas was undoubtedly the sovereign nation of Mexico, which still considered Texas a part of their nation.
Anti-Slavery Northerners:
Northerners – especially Whigs, but also free soil Democrats – opposed the annexation of Texas as well. This was largely because they saw in Texas a new slave state, and perhaps more than one!

3. The issue of slavery divided the party
Both Martin Van Buren and Henry Clay refused to state with any clarity that they would annex Texas while they were running for President in As a result, they lost out. Van Buren – who would go on to run for President as a Free-Soiler – lost out on the Democratic nomination to “dark horse” candidate James K. Polk. Clay, meanwhile, would lose the election. The principle reason: American favored expansion and considered it our “Manifest Destiny” to control the future of the West, including Texas. Slavery or no slavery!

4. The free-soil party: The Liberty party
When Henry Clay announced that he would support the annexation of Texas in on uncertain terms, he lost the support of a small percentage of his own party, the Whigs. While it may not have been a huge number of votes, they were critical to Clay’s plan for victory. He lost several states’ electoral college votes because some of his former supporters chose to support the Liberty Party – which opposed slavery and opposed the annexation of Texas.

5. “Fifty-four Forty or fight!”
The jingoist campaign slogan of James K. Polk was “Fifty-Four Forty or Fight!” It was a direct threat to England, with whom the United States had peacefully occupied the Oregon Territory since 1818… Polk demanded that England cede all territory in the Oregon Country to the United States, and threatened war if they did not give up. Happily, after the war, Polk would ease off this demand. James Buchanan, his Secretary of State, would negotiate a treaty with England in which the US retained the Southern portion of the Oregon Country, and the English would retain the northern parts.

6. President John Tyler of Virginia
It was President John Tyler of Virginia who formally annexed Texas in 1845 – at the tale end of his accidental Presidency. Tyler insisted that the boundary between the United States and Mexico was now the Rio Grande River. Mexicans insisted that Texas’ border had always been at the Nueces River, hundreds of miles farther north. Mexico objected to the annexation of Texas no matter where the boundary was – but the Rio Grande as the border added insult to injury.

7. The rebuffed offer of John Slidell
John Slidell was sent to Mexico by President James K. Polk in order to acquire California. He offered millions of dollars for the land – but ever at that, it was a low-ball offer. (He offered about $25 Million. At the end of the Mexican-American War, Mexico would lose California and all of the Mexican Cession for just $20 Million.) Polk was angered that Mexican government officials refused to meet with Slidell, and that they imprisoned him when he refused to leave the country.

8. General zachary taylor provokes war
James K. Polk essentially gave Zachary Taylor the order to provoke the Mexican-American War. Polk ordered Taylor to march into the disputed territory between the Nueces River and the Rio Grande along the border between Texas and Mexico. Indeed, Taylor’s men sought out the Mexican Army. When shots were exchanged, Polk insisted that this was justification for war, and went before Congress to seek a formal declaration.

9. Congress Declared War against Mexico in 1846 – with very few dissenting votes.
The Senate voted 40 – 2 in favor of war with Mexico. The House of Representatives voted to declare war 174 – 14.

10. The Three pronged Attack on Mexico, 1846 - 1848
The United States invaded Mexico from the Texas border and moved to the south, taking Monterrey and Buena Vista rapidly.
A United States Naval expedition landed at Veracruz, Mexico and proceeded to attack Mexico City. Mexico City fell in the autumn of
The United States organized an expedition to seize California from the onset of the war, which was successful.

11. Frederick Douglass condemned the war, which he believed was waged to spread Slavery.
Frederick Douglass believed that the Mexican-American War was provoke in order to expand the slave territory of the United States. He sympathized with the Mexicans for a variety of reasons, not the least of which was the fact that Mexico had forbidden slavery throughout their country in (including in Texas!) When Texas was annexed, Douglass – along with many Northerners and free-soilers – feared that four or more slave states might be carved from the region. Now, he feared that even more Mexican land would become slave territory.

12. California’s bear flag republic
Stephen Kearny led a small force of Americans to seize California, where John C. Fremont – leader of an American militia – had already declared California an independent republic…

13. The Treaty of Guadalupe-hidalgo ends the war in 1848
Mexico ceded over 500,000 square miles of land including parts of present day New Mexico, Arizona, Colorado, Wyoming, Nevada, and California.
Mexico accepted the boundary between Texas and Mexico as the Rio Grande River, as the United States had insisted before the conflict.
The United States paid Mexico approximately $18.25 Million for the land and forgave some Mexican debts owed to Texans.