The Lower Rio Grande Valley (), often referred to as the Rio Grande Valley (RGV) of South Texas, is a metropolitan region located in the southernmost part of Texas. It is located along the border of Texas with Mexico located in a floodplain of the Rio Grande near its mouth. It consists of the Brownsville-Harlingen and McAllen-Edinburg-Mission metropolitan areas, and the Rio Grande City-Roma and Raymondville micropolitan areas. The area is generally bilingual in English and Spanish, with a fair amount of Spanglish due to the region's diverse history and transborder agglomerations. It is home to some of the poorest cities in the United States, as well as many unincorporated, persistent poverty communities called colonias. A large seasonal influx occurs of "winter Texans" – people who come down from the north for the winter and then return north before summer arrives.
History
Pre-Spanish colonization
Native peoples lived in small tribes in the area before the Spanish conquest. The native tribes in South Texas were known to be hunter-gatherer peoples. The area was known for its smaller nomadic tribes collectively called Coahuiltecan. Native archaeological excavations near Brownsville have shown evidence of prehistoric shell trading.
Spanish colonization
Initially, the Spanish had a hard time conquering the area due to the differences in native languages, so they mainly focused on the coast of the Gulf of Mexico also known as the Seno Mexicano. Also, a major conflict existed on who would conquer the region. Antonio Ladrón de Guevara wanted to colonize the region, but the Viceroy of New Spain José Tienda de Cuervo doubted Ladrón de Guevara's character, eventually leading to a royal Spanish declaration preventing Ladrón de Guevara from participating in colonization efforts.
The first villas in the region were settled in Laredo and Reynosa in 1767. In 1805, the Spanish government solidified the autonomy of the region by defining the territory of Nuevo Santander as south of the colony of Tejas from the Nueces River south to Tampico, Charcas, and Valles. The local government of the region had a rough start with various indigenous wars up until 1812. In 1821 after the Mexican War of Independence, the state was renamed Tamaulipas.
Republic of Texas and annexation by the United States
The Texas Revolution of 1835–1836 put the majority of what is now called the Rio Grande Valley under contested Texan sovereignty. The area also became a thoroughfare for runaway slaves fleeing to Mexico.
In 1844, the United States under President James K. Polk annexed the Republic of Texas, against British and Mexican sentiments, contributing to the onset of the Mexican–American War. The area along the Rio Grande was the source of several major battles, including the Battle of Resaca de la Palma near Brownsville. The war ended in 1848 with the signing of the Treaty of Guadalupe Hidalgo which defined the United States' southern border as the Rio Grande. The change in government led to a mass migration from Tamaulipas to the United States side of the river.
From the end of the Mexican-American War, the population of the Valley began to grow, and farmers began to raise cattle in the area. Despite the end of the formal war in 1848, interracial strife continued between native peoples and the white settlers over land through the 1920s.
Early 1900s and the Mexican Revolution
At the turn of the 20th century trade and immigration between Mexico and the United States was a normal part of society. The development of the St. Louis, Brownsville, and Mexico Railway in 1903 and the irrigation of the Rio Grande allowed the Rio Grande Valley to develop into profitable farmland. Droughts in the 1890s and early 1900s caused smaller farmers and cattle ranchers to lose their lands. Rich white settlers brought by the railroad bought the land and displaced the Tejano ranchers.
Meanwhile, across the river, Mexico was dealing with the Mexican Revolution. The revolution spilled over the border through cross-border supply raids, and in response President Taft sent the United States Army into the region beginning in 1911 and continuing until 1916 when the majority of the United States armed forces were stationed in the region. Texas governor Oscar Colquitt also sent the Texas Rangers into the area to keep the peace between Mexicans and Americans.
The region played host to several well-known conflicts including the backlash from the Plan of San Diego, and the racially fueled violence of Texas Ranger Harry Ransom. In 1921 the United States Border Patrol came to the region with less than 10 officers. Initially the agency was focused on import and export business, especially alcohol during Prohibition in the United States, but later moved to detaining illegal aliens.
The region had a significant increase of Border Patrol agents during World War I in conjunction with the Zimmermann Telegram. The Texas Rangers also increased their presence as law enforcement in the region with a new class of Ranger that focused on determining Tejano loyalty. They were often violent, carrying out retaliatory murders. They were never held accountable to the law even though charges were brought in the Texas senate.
There were two major military training facilities in the Valley in Brownsville and Harlingen during World War II.
Post-World War II to present
The North American Free Trade Agreement, also known as NAFTA, was established in 1994 as a trade agreement between the three North American countries, The United States, Mexico, and Canada. NAFTA was supposed to increase trade with Mexico as they lowered or eliminated tariffs on Mexican goods. Exports and imports tripled in the region and accounted for a trade surplus of $75 billion. The Rio Grande Valley benefited from NAFTA in retail, manufacturing, and transportation. Due to the influx of jobs and exportation, many people migrated to the RGV, both documented and undocumented. According to Akinloye Akindayomi in Drug violence in Mexico and its impact on the fiscal realities of border cities in Texas: evidence from Rio Grande Valley counties, NAFTA also indirectly aids the rise in immigration and drug smuggling practices between cartels in the region, with cartels profiting with over $80 billion. The Trump Administration decided to make new accords with Mexico and Canada and replaced NAFTA with the new trade agreement, United States–Mexico–Canada Agreement (USMCA) in 2018.
After the September 11 attacks, the Customs Border Security Act of 2001 established United States Border Patrol interior checkpoints with some situated at the north end of the Rio Grande Valley.
The organization We Build the Wall built a section of the border wall in the Valley. Residents expressed concerns about the project including the site's proximity to the National Butterfly Center and the Rio Grande with its potential for seasonal flooding. The U.S. Section of the International Boundary and Water Commission ordered We Build the Wall to stop until they can review whether or not the construction violates a Treaty to resolve pending boundary differences and maintain the Rio Grande and Colorado River as the international boundary between the United States and Mexico signed in 1970.
Geography
The Rio Grande Valley is not a true valley, but a river delta. "Valley" is often used in the western United States to refer to a large expanse with rivers. Most such valleys, including the Rio Grande, have good agricultural production. Early 20th-century land developers, attempting to capitalize on unclaimed land, used the name "Magic Valley" to attract settlers and appeal to investors. The Rio Grande Valley is also called El Valle, the Spanish translation of "the valley", by those who live there. The region is within four counties in Texas: Starr, Hidalgo, Willacy, and Cameron.
Major settlements The largest city is Brownsville (Cameron County), followed by McAllen (Hidalgo County). Other major cities include Harlingen, San Benito, Edinburg, Mission, Rio Grande City, Raymondville, Weslaco, Hidalgo, Pharr, and Starbase.
Demographics As of 2025, the U.S. Census Bureau estimated the population of the Rio Grande Valley at 1,441,785. Hidalgo County has the largest population with an estimate of 921,319. Cameron County has the second-highest population estimated at 433,946. Starr County has the third-largest population estimated at 66,319. Willacy County has the fourth-largest population estimated at 19,971.
According to the U.S. Census Bureau, in 2020, 89 percent of Cameron County, 92 percent of Hidalgo County, 97 percent of Starr County, and 88 percent of Willacy County are Hispanic.
Colonias
The major metropolitan areas in the Rio Grande Valley are surrounded by smaller rural communities called colonias. These communities are primarily poor and Hispanic. The areas often lack basic services like sanitation and sewage, and suffer from flooding. Many of these colonias are mixes of mobile homes and self-constructed houses owned by the residents. The Bracero program enacted in the 1940s allowed Mexicans to cross the border and work in the agricultural fields. Most worked in the Rio Grande Valley, and due to a shortage of affordable houses, developers started selling them land in unincorporated areas; these clusters of homes over time became what are now known as colonias. According to the Housing Assistance Council, a nonprofit organization that tracks rural housing, approximately 1.6 million people live in 1,500 recognized colonias alongside the Mexican border.
Language use The residents of the Lower Rio Grande Valley are generally bilingual in English and Spanish often mixing into Spanglish depending on demographics and context. Government statistics for the region are often underreported due to underlying immigration issues.
The Spanish language plays an important role in all aspects of life. In 1982 a statistically significant majority of people in the Rio Grande Valley spoke Spanish. People speak Spanish to communicate in all aspects of life including business, government, and at home.
+ 2017 United States Census American Community Survey estimatesCameron CountyHidalgo CountyStarr CountyWillacy CountyPopulation 5 years and older384,007759,14356,97220,442Speaks English only102,074119,4892,0728,252Language other than English281,933639,65454,90012,190Spanish278,451631,63854,83812,005Other Indo-European languages1,3022,1263155Asian and Pacific Islander languages1,5115,4605322Other languages66943068
People often prefer Spanish to English when interacting with government officials as seen in the response to the region's 2018 flooding.
Religion The Catholic Church has been present in the Rio Grande Valley since the Spanish colonization of the region. In San Juan, Texas the Basilica of the National Shrine of Our Lady of San Juan del Valle is a major Catholic shrine.
One of the offshoots of the Catholic Church, worship of Santa Muerte, has a small but significant following in the valley. There has been public outcry against followers erecting shrines at their homes and in public places. In 2015, a Santa Muerte statue was involved with a bomb scare in San Benito, Texas. This followed the desecration of a Santa Muerte statue in the San Benito Municipal Cemetery in January of the same year.
In addition to the Catholic Church, several other Christian denominations are present in the Rio Grande Valley, including several organized Protestant churches in the Lower Rio Grande Valley.Grammich, C., Hadaway, K., Houseal, R., Jones, D. E., Krindatch, A., Stanley, R., & Taylor, R. H. (2018, December 11). U.S. Religion Census Religious Congregations and Membership Study, 2010 (County File). There are also 26 congregations of the Church of Jesus Christ of Latter-day Saints with about 17,000 members. Muslim, Jewish, Hindu, Buddhist, Sikh, and Baháʼí Faith communities thrive in the Rio Grande Valley.
Culture