Why did many Mexican Americans lose their land after the Southwest joined the Union???

been deprived of their land, and found themselves living unprotected in an often hostile region.

Explanation:

Under the treaty that ended the Mexican War, most of the Mexicans who lived in the new United States territories became U.S. citizens. The treaty also guaranteed their safety and property rights, "as if the [property] belonged to citizens of the U.S. according to the principles of the Constitution." In practice, however, the new territories were far from the centers of U.S. government, and these guarantees were not reliably enforced. By the end of the 19th century, many Mexican Americans had been deprived of their land, and found themselves living unprotected in an often hostile region.

At the turn of the 20th century, the borderlands between Mexico and the U.S. were torn by political and social instability. As more immigrants crossed the border, some were preyed upon by bandits and rustlers. Once in the U.S., they had to face harsh weather, an uncertain economy, and the possibility of attacks by both longtime citizens and Native American raiders. Law enforcement was scarce, and justice was often rough and quickly executed. To make things worse, some lawmen were said to be as much of a threat to Mexican Americans as the criminals they were sent to arrest. The Texas Rangers came in for especially fierce criticism. In the " Corrido de los rangers," a singer describes a gunfight between city officials and Texas Rangers in the streets of Brownsville, Texas.

Mexican boy playing guitar in room of corral.

Some Mexican Americans embraced a new type of popular music--the corrido, or border ballad. Shaped by hard times and long distances, these storytelling songs were much like musical newspapers and carried news of current events and popular legends around the border region. Passed from one singer to another, many of these songs survive to the present day. "Versos del mojado" describes the troubles faced by a new immigrant in Texas.

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