Changing the Map of North America

In spring 1846, disputes over US and Mexican land ownership, in particular the US annexation of Texas, came to a head when Congress declared war on Mexico. The first major battles had already occurred at Palo Alto and Resaca de la Palma. More battles ensued as US troops fought overland to Mexico City. The Treaty of Guadalupe Hidalgo ended the war on February 2, 1848, and established the Rio Grande as the border. Stories of the war are told in parks across the country.

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Last updated: June 11, 2019