Due to the possibility of violence spilling over into the U.S., in 1916 the United States Army establishes a series of camps and forts along the border. A camp was established just east of what is now downtown Weslaco. Called Camp Llano Grande 12,000 soldiers built a semi-permanent camp at the former town of Llano Grande. The camp was used to train and prepare the troops for the fighting in Europe in WW1. The troops in the area mostly consisted of cavalry with a few components of artillery. It appears as though some of the soldiers stationed there during this time eventually made the Valley their permanent home.

In 1919 investors W.E. Stewart, Ed Couch, and R.L. Reeves decided to create another town between Donna and Mercedes. Despite opposition to the creation of a town in this location, the 3 investors moved forward with their plans and formally have plans drawn for what will become known as the city of Weslaco. The name Weslaco is chosen from W.E.S(tewart) LA(nd) CO(mpany). By December lots are being sold and the city begins development.
Large-Fire-11921 LARGE FIRE

In 1921 a large fire destroys many buildings in the new town. Due to this, a new city ordinance required local buildings to be constructed of brick. An ordinance also states that the land north of the railroad tracks be designated for Hispanic residences and businesses (Mexican Town), while the land south of the tracks was to be used for Anglo residents and businesses (American Town).

1921 Weslaco ISD is established. Stephen F. Austin grammar school is opened as the first school building in the district. Between 1922-23 Weslaco High School opens, and in 1925 the Jr. High opens its doors. There are separate schools for the white children (Stephen F. Austin), Hispanic children (North Ward is later known as Horton), and African-American children (Beatrice Allen on Pino Street). In 1961 Weslaco Schools are officially integrated.

The Rio Grande Valley Citrus Growers Association is established in 1932 with its headquarters located in Weslaco. This leads to the creation of the Texsun citrus complex in the city. Texian became the world's largest producer of juice and will remain a vital part of the economy in Weslaco until 1992.

Between 1932 and 1952, Weslaco hosted the annual Fruit and Vegetable Style Show in which participants created themed costumes from local plants. These were sewn together in the city ice house in order to keep the leaves from wilting.


At the battle of Iwo Jima, Weslaco native Harlon Block participates in the famous flag-raising atop Mt. Suribachi. This image would become an iconic photo from the war and be used to promote War Bond sales throughout the country.

Bobby Lackey becomes an all-American in football, all-state in basketball, and all-district in baseball while attending Weslaco High School. He helps the Weslaco Panthers make four straight playoff appearances, including a trip to the state semi-finals in 1955 before attending the University of Texas. While attending UT, he becomes their starting quarterback in the late 1950s and was the team's top scorer in 1958 and 1959. He helps lead the Longhorns to win a share of the 1959 Southwest Conference championship. Lackey was also the first Longhorn to ever appear on the cover of Sports Illustrated