|Source: The Economist
In early February 1848, following a short and one-sided war, México agreed to cede more than half its territory to the United States. An area covering most of present-day Arizona, California, Nevada, New Mexico and Utah, plus parts of several other states, was handed over to the US.
The rebellious state of Tejas, which had declared its independence from México in 1836, was recognised as American soil too.
But a century and a half later, communities have proved more durable than borders. The counties with the highest concentration of Mexicans (as defined by ethnicity, rather than citizenship) overlap closely with the area that belonged to México before the great US land-grab of 1848. Some are recent arrivals; others trace their roots to long before the map was redrawn. They didn’t jump the border—it jumped them.