El Horcon Tract and Rio Rico
Mercedes, Hidalgo County, Texas
Marker Inscription
The Treaty of Guadalupe Hidalgo which ended the Mexican War (1846-48) designated the main channel of the Rio Grande as the Mexico-U.S. boundary. Disputes arising from frequent changes in the river's course led to the Treaty of 1884 which recognized only those river diversions resulting from natural occurences. The International Boundary Commission was established in 1889 to administer the Treaty of 1884. In 1906 the American Rio Grande Land and Irrigation Company dug an unauthorized canal about two miles south of here which altered the natural course of the Rio Grande. As a result, a 419-acre section of U.S. property called El Horcon tract was isolated south of the river. Although still U.S. territory according to the Treaty of 1884, the tract and the popular gambling and resort community of Rio Rico which flourished there during the 1920s and 1930s became increasingly subject to Mexican administration and jurisdiction. After the U.S. granted Mexico territorial rights over El Horcon tract and Rio Rico in 1970, a native of Rio Rico sued the U.S. government to guarantee his U.S. citizenship. This lawsuit began an eight-year legal battle that eventually led to U.S. citizenship for about 200 people born in Rio Rico prior to 1970. (1994)
Erected by Texas Historical Commission
The Story
The 1848 Treaty of Guadalupe Hidalgo fixed the Rio Grande's main channel as the U.S.–Mexico line, but the river's wandering course bred endless disputes. In 1906 an unauthorized canal shifted the Rio Grande and stranded the 419-acre El Horcon tract—home to the freewheeling resort of Rio Rico—on the Mexican side, where it drifted under Mexican control. After the U.S. ceded the tract to Mexico in 1970, a Rio Rico native's lawsuit secured U.S. citizenship for some 200 people born there before the transfer.
Why it matters
This shifting patch of riverbank shows how a line drawn on water could redraw people's nationality, a vivid case of how the U.S.–Mexico border shaped—and unsettled—the citizenship of those living along it.
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Related events
- · Treaty of Guadalupe Hidalgo
- · Treaty of 1884
Themes & tags
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