How Mexican immigration helped make America great

SMU History Professor Neil Foley talks about the historic relationship between Mexico and the U.S. and how Mexican immigration in the 1840s helped make America great.

By Annabelle Quince and Keri Phillips

It's obvious from the names of some of America's biggest cities that they have a Spanish-speaking heritage. Settlements like Santa Fe, San Antonio, Los Angeles, and San Diego fall within the swathes of south-west America that were colonised by Spain and were then, for centuries, part of Mexico.

However, after Mexico's defeat in the American–Mexico war of 1846–1848 the border shifted almost a thousand miles to the south, as academic Neil Foley from the Southern Methodist University explains.

'Out of that northern half that was seized after the US–Mexico war ... the United States was able to carve out territories that then became six complete states—the border states of California, Arizona, New Mexico and Texas, in addition to Nevada and Utah—and parts of Colorado, Wyoming, Arkansas and Oklahoma,' he says.

'That's a huge, huge chunk of real estate that overnight made Mexican citizens American citizens.

'According to the Treaty of Guadalupe Hidalgo, the roughly 100,000 Mexicans living north of the new international boundary were given one year to declare their Mexican citizenship. If they didn't declare their Mexican citizenship they automatically became US citizens.'

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