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In which John Green teaches you about the Mexican-American War in the late 1840s and the expansion of the United States into the western end of North America. In this episode of Crash Course, US territory finally reaches from the Atlantic coast to the Pacific Ocean. After Oregon was secured from the UK and the southwest was ceded by Mexico, that is. Famous Americans abound in this episode, including James K Polk (Young Hickory, Napoleon of the Stump), Martin Van Buren, Zachary Taylor, and Winfield Scott. You'll also learn about the California Gold Rush of 1848, and California's admission as a state, which necessitated the Compromise of 1850. Once more slavery is a crucial issue. Something is going to have to be done about slavery, I think. Maybe it will come to a head next week. Support CrashCourse on Patreon:

Hey teachers and students - Check out CommonLit's free collection of reading passages and curriculum resources to learn more about the events of this episode. America’s Westward expansion was fueled by both Manifest Destiny and a desire to grow the nation and its resources — though at a cost:

Introduction: Texas & California 00:00
Manifest Destiny 0:41
The Oregon Trail 1:21
Western Settlements 1:37
How Texas Became a State 2:02
Polk's Wars for Expansion 4:04
Critics of the Mexican-American War 4:51
The End of the Mexican-American War 5:32
The Know-Nothings 6:20
The California Gold Rush 7:26
Mystery Document 8:08
California & the Free Soil Party 9:21
California Statehood and the Compromise of 1850 10:25
The Problem with Manifest Destiny 11:40
Credits 12:14

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 Intro (0:00)

Hi, I'm John Green. This is Crash Course US History, and today we're gonna discuss how The United States came to acquire two of its largest States - Texas, and there is another one.

Past John: "Mr. Green! Mr. Green! I believe the answer you're looking for... is Alaska."

Present John: Oh, me from the past, as you can clearly tell from the globe, Alaskan statehood never happened. No, I am referring, of course, to California.

Stan, are we using your computer today? Doh, Stan!

We talked about Western expansion a few of times here on Crash Course, but its usually about, like, Kentucky or Ohio. This time we're going really West, I mean, not like Hawaii west, but sea to shining sea West.

[intro music]

 Manifest Destiny (0:41)

So you might remember that journalist John O'Sullivan coined the phrase "manifest destiny" to describe America's God given right to take over all the land between the Atlantic and Pacific Oceans regardless of who might be living there. Sorry, Native Americans, Mexicans, French fur trappers, beavers, bison, prairie dogs, passenger pigeons.

I'm not gonna give so far as to give God credit about America's internal imperialism but I will say our expansion had a lot to do with economics, especially when you consider Jefferson's ideas about the empire of liberty. Dan, did I just say "liberty?" That means technically I also have to talk about slavery but we're gonna kick the slavery can down the road until later in the show, just like American politicians did in the 19th century.

By 1860 nearly 300,000 people had made trip that has since then been immortalized by the classic educational video game Oregon Trail, which by the way is inaccurate in the sense that a family of six, even a very hungry one, cannot eat a buffalo. But is extremely accurate in that a lot of people died of dysentery and cholera. Frickin' disease.

So Oregon at the time was jointly controlled by the US and Britain. Northern Mexico at the time included what are now Texas, Arizona, Utah, Nevada, New Mexico, and California. But New Mexico and California were the only two, with like big settlements - about 30,000 Mexicans lived in New Mexico and about 3,500 in California, and in both places they were outnumbered by Native Americans. Ok. let's go to the Thought Bubble.

 Thought Bubble (1:59)

When Mexico became independent there were only about 2,000 Tejanos there, so, to encourage economic development, Mexico's government granted a huge tract of land to Moses Austin. Austin's son Steven made a tidy profit selling off smaller parcels of that land until there were 7,000 American Americans there. This made Mexico nervous, so, backpedaling furiously, Mexico annulled the land contracts and banned further immigration into Texas.

Even though slavery was already abolished in Mexico, up to now they had allowed Americans to bring slaves. Austin, joined by some Tejano elites demanded greater autonomy and the right to use slave labor. Thinking the better of it, Mexican general Antonio López de Santa Anna decided to assert control over the rest of the territory with an army turning the elites' demand for autonomy into a full-scale revolt for independence.

On March 13th, 1836, Santa Anna defeated the American defenders of the Alamo, killing 187 or 188, sources differ, Americans including Davy Crockett. The Texas rebels would "remember the Alamo," and come back to defeat Santa Anna at the Battle of San Jacinto, and Mexico was forced to recognize Texas' independence.

So Texas became the Lone Star Republic and quickly decided that it would much better to be a less lonely star and join the United States. So in 1837 Texas' congress called for union, but all they heard back was "Not so fast, Texas." Why? Because Texas wanted to be a slave state, and adding another slave state would disrupt the balance in the Senate, so Jackson and Van Buren did what good politicians always do: they ignored Texas.

And then after Martin Van Buren wrote a letter denouncing any plans to annex Texas on the grounds it would probably provoke a war, Democratic convention southerners threw their support behind slave-holding Andrew Jackson pal, James K. Polk. Polk just managed to get a presidential victory over perennial almost-president Henry Clay and seeing the writing on the wall, Congress annexed Texas in March of 1845, days before Polk took office. Congress then forged an agreement with Britain to divide Oregon at the 49th parallel, which restored the slave state-free state balance in the Senate. Thanks, Thought Bubble.

 The Mexican-American War (3:58)

Hey Stan, can I get the foreshadowing filter? I wonder if we're going to be able to keep that slave state-free state balance... forever.

The land-hungry James K. Polk had another goal as president: acquire California from Mexico. He tried to purchase it from Mexico, but they were like, "No," which is Spanish for no. So, Polk decided to do things the hard way. He sent troops under future president Zachary Taylor into this disputed border region. As expected - by which I mean intended - fighting broke out between American and Mexican forces. Polk, in calling for a declaration of war, proclaimed that the Mexicans had quote, "shed blood upon American soil," although the soil in question was arguably not American, unless you think of America as being, you know, all of this.

The majority of Americans supported this war, although, to be fair, a majority of Americans will support almost any war. I'm sorry, but it is - it's true. At least at first!

It was the first war fought by American troops primarily on foreign soil, as most of the fighting was done in Mexico. Among the dissenters was a Massachusetts transcendentalist, who was probably better known than the war itself. Henry David Thoreau was in fact thrown in jail for refusing to pay taxes in protest of the war, and wrote On Civil Disobedience in his defense, which many American high schools are assigned to read and expected not to understand, lest they take the message to heart and stop doing assignments like reading On Civil Disobedience.

Another critic was concerned about the increase in executive power that Polk seemed to show, saying, "Allow the president to invade a neighboring country whenever he shall deem it necessary to repel an invasion, and you allow him to make war at pleasure." That critic was none other than noted peacenik Abraham Lincoln, who would go on to do more to expand executive power than any president in the 19th century, except maybe Andrew Jackson.

Right, so Santa Anna's army was defeated in February 1847, but Mexico refused to give up, so Winfield Scott, who had the unfortunate nickname "Old Fuss and Feathers," captured Mexico City itself in September. A final peace treaty - the Peace Treaty of Guadalupe Hidalgo - was signed in 1848, under which Mexico confirmed the annexation of Texas and further ceded California as well as several other places that would later become states but we couldn't fit on the map.

In return, the U.S. paid Mexico $15 million and agreed to a no-backsies deal in re: Texas, thereby freeing Mexico from the shackles of Amarillo. I'm sorry, Amerillans. No, I'm not. I am. I'm - I am. I'm not. I am!

This is great, Stan, the people of Amarillo hate me, also the people of New Jersey, Alaska is in the green parts of not-America. We don't even have Arizona and New Mexico on the chalkboard. Pretty soon, I will have alienated everyone.

 Nativism (6:20)

Anyway, thanks to the land from Mexico, our dream of expanding from the Atlantic to the Pacific was finally complete, and as always happens when dreams come true, trouble started. After the Treaty of Guadalupe Hidalgo, between 75,000 and 100,000 Spanish-speaking Mexicans and 150,000 Native Americans were under the jurisdiction of the United States. Despite the fact that the treaty granted Spanish-descended Mexican male citizens legal and property rights, the Mexicans were still seen as inferior to Anglo-Saxons, whose manifest destiny was, of course, to overspread the continent.

And the fact that these Mexicans were Catholic didn't help either, especially because in the eastern part of the United States, there was a rising tide of anti-Catholic, anti-immigrant sentiment known as nativism. And there was a new political party, the American Party, dedicated entirely to such sentiment. They were referred to as the Know-Nothings, because when you asked them about their politics, they would answer that they didn't know anything. And, indeed, they didn't.

This was not an expert branding strategy, although they did manage to win an unexpected number of local offices in a state heralded for its ignorance, Massachusetts. You thought I was going to say New Jersey, but I'm trying to make nice with the New Jersey people because they take it pretty personally.

Meanwhile, in California, there weren't enough white, English-speaking American residents to apply for statehood until gold was discovered in 1848, leading, of course, to San Francisco's NFL team: the San Francisco 48ers. By 1852, the non-Indian population in California had risen from 15,000 to 200,000 and it was 360,000 on the eve of the Civil War.

Now, not all of those migrants - mainly young men seeking their fortunes - were white. Nearly 25,000 Chinese people migrated to California, most as contract workers working for mining and railroad companies. And there were women, too, who ran restaurants and worked as cooks and laundresses and prostitutes, but the ratio of men to women in California in 1860 was 3 to 1.

Ahh, schmerg, it's time for the Mystery Document?

 Mystery Document (8:08)

The rules here are simple. I read the Mystery Document, and I'm either shocked by electricity or by the fact that I got it right.

"We would beg to remind you that when your nation was a wilderness, and the nation from which you sprung barbarous, we exercised most of the arts and virtues of civilized life; that we are possessed of a language and a literature, and that men skilled in science and the arts are numerous among us; that the productions of our manufactories, our sail and workshops, form no small share of commerce of the world; and that for centuries, colleges, schools, charitable institutions, asylums, and hospital shave been as common as in your own land (...) And we beg to remark, that so far as the history of our race in California goes, it stamps with the test of truth that we are not the degraded race you would make us."

So, it's someone who said "We had a great civilization when you were a wilderness," plus they called us barbarous, so it's either ancient Rome or China. I'm gonna lean toward China. That only gets me halfway there. Now I have to think of the name of the person and I [sings] don't know any famous people from mid-19th century China who lived in the U.S. People say I can't sing.

Norman Asing?! Who the hell is Norman Asing? 'S does is - ahhAAAAAAAAAAAAHHHHHHH!

 Free Soil and the Missouri Compromise (9:20)

So these days, California is known for its groovy, laid-back, "Oh, your back hurts? Here's some pot" attitude, but that was not the case in the 19th century. The California constitution of 1850 limited civil participation to whites. No Asians, no black people or Native Americans could vote or testify in court. Indians were kicked off their land if it had any mineral value, and thousands of their orphaned children were sold as slaves. And all of this led to the Indian population of California dropping from 150,000 to about 30,000 between 1848 and 1860.

So it wasn't at all clear whether California was the kind of place to be admitted to the U.S. as a free state or as a slave state. The Missouri Compromise was of no help here, because half of California is below the 36°30′ line, and half is above it.

So, a new Free Soil Party formed in 1848 calling for the limiting of slavery's expansion in the West so that it could be open for white people to live and work. I just want to be clear that most of the people who were for limiting slavery were not, like, un-racist. So they nominated the admirably whiskered Martin Van Buren for the presidency, and Van Buren and Democratic nominee Lewis Cass then split the northern vote, allowing the aforementioned Zachary Taylor to win.

So, in 1850, when California finally did ask to be admitted into the Union, it was as a free state. Southerners freaked out, because they saw it as the beginning of the end of slavery, but then, to the rescue came Henry Clay for his last hurrah. He said, "we can kick this problem down the road once more" and brokered a four-part plan that became known rather anticlimactically as the Compromise of 1850. Historians, can you name nothing?!

The four points were:

1) California would be admitted as a free state,

2) the slave trade - but not slavery - would be outlawed in Washington D.C.,

3) a new super harsh fugitive slave law would be enacted, and

4) popular sovereignty. The idea was that in the remaining territories taken from Mexico, the local white inhabitants could decide for themselves whether the state would be slave or free when it applied to be part of the United States. Ah, the Compromise of 1850. A great reminder that nothing protects the rights of minorities like the tyranny of the majority.

There was a huge debate over the bill in which noted asshat John C. Calhoun was so sick that he had to have his pro-slavery anti-Compromise remarks read by a colleague. On the other side, New York Senator William Seward, an abolitionist, also argued against compromise, based on slavery being - you know - wrong. But eventually, the Compromise did pass, thus averting a greater crisis for 10 whole years.

Ralph Waldo Emerson predicted that if the United States acquired part of Mexico, it would be like swallowing arsenic. And indeed, arsenic can be a slow-acting poison. Now, I don't think Ralph Waldo Emerson was a good enough writer to have thought that far ahead, but he was right. Some people say that manifest destiny made the Civil War inevitable, but as we'll see next week, what really made the Civil War inevitable was slavery.

But we see in the story of manifest destiny the underlying problem: the United States didn't govern according to its own ideals. It didn't extend liberties to Native Americans or Mexican Americans, or immigrant populations, or slaves. Thanks for watching, and we'll see you next week... when things will get much worse!

 Credits (12:14)

Crash Course is produced and directed by Stan Muller. Our script supervisor is Meredith Danko. The show is written by my high school history teacher Raoul Meyer and myself. Our associate producer is Danica Johnson. And our graphics team is Thought Cafe.

If you'd like to contribute to the Libertage, you can suggest captions. You can also ask questions in comments where they will be answered by our team of historians.

Thank you for watching Crash Course, and as we say in my home town, don't forget to be awesome.