WHAT IF...MEXICO DEFEATED THE UNITED STATES?

Could Mexico have claimed vast swathes of territory, including the potentially gold-rich California, in a huge blow to US expansion?

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What was the background to the MexicanAmerican War of 1846-48?

The United States in the early 19th century had a rapidly growing population, particularly in the west. [This] put it on a collision course with the Republic of Mexico, which had acquired its independence in the 1820s and claimed much of the territory in what is now the southwest of the United States, and indeed the Pacific Coast of the United States. So in the 1840s the US found itself on a potential road to conflict with both Mexico and Britain in what’s today the Pacific Northwest. That’s the big picture. The more proximate cause is that the American settlers in the Mexican province of Texas in 1836 rebelled, declared independence, fought a short but relatively bloody war of independence and achieved their independence. And then the United States, in 1846, annexed Texas, and that set the war in motion between 1846 and 1848.

What happened from 1846 to 1848?

The United States and Mexico fought on a number of fronts. American troops invaded what we now think of as modern Mexico [through Texas]. Other American troops went west to California. And then, in probably the big campaign of the war, General Winfield Scott landed at Veracruz and actually went inland through the heart of Mexico, capturing Mexico City, which the Duke of Wellington called the greatest campaign in history. So the Americans invaded Mexico, or seized Mexican territory, on three fronts.

Was this conflict a one-sided fight in favour of the Americans?