Mexican-origin and the USA - a (somewhat depressing) #Visualization

From The Economist,

On February 2nd 1848 [...] An area covering most of present-day Arizona, California, Nevada, New Mexico and Utah, plus parts of several other states, was handed over to gringolandia. The rebellious state of Tejas, which had declared its independence from Mexico 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 Mexico before the great gringo 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.

For a history of the Mexican (as part of the wider Hispanic) experience in America, I can't recommend Felipe Fernández-Armesto's book Our America: A Hispanic History of the United States
 highly enough. He is a Spanish historian at The University of Notre Dame, and his relentless description of what was as much a Spanish colonial enterprise in the south as a British/European westward march is a must read.  From the New York Times review

Time and again, [the American borders] were traced through rebellion, looting and murder. Spanish forces, Mexican armies and United States troops competed ferociously, with opportunists and landowners ready to join the shooting. In 1819, Spain renounced claims to Florida while the United States renounced Texas. But Mexico’s independence from Spain resulted in its losing Texas to immigrants from the United States, the “illegal aliens” of their day. John Quincy Adams said, “In this war, the flag of liberty will be that of Mexico, and ours, I blush to say, the flag of slavery.” Stephen Austin, on the other hand, saw the war between the Texans and Mexicans as one “of barbarism and of despotic principles, waged by the mongrel Spanish-Indian and Negro race against civilization and the Anglo-­American race.”

Look at the map again - and feel a wee bit more depressed about it...