The history of McAllen began in 1904, when John McAllen, a Scottish settler and rancher, founded a settlement on his land together with other partners. Initially, it was known as West McAllen. In 1907, a competing town called East McAllen emerged nearby; however, soon after in 1910, both settlements merged. The City of McAllen was officially incorporated on February 21, 1911.
A key role in the city's development was played by the arrival of the St. Louis, Brownsville & Mexico Railway in 1905. This event provided essential transport links and stimulated commercial activity, transforming McAllen into a significant logistical hub. The geographical proximity to the Mexican border (approximately 13 km) also became a powerful growth factor, facilitating trade between the two countries. The city quickly turned into an important point for the import and export of goods.
From the very beginning, McAllen's economy was closely tied to agriculture. Thanks to the development of irrigation systems in the Rio Grande Valley, the region became a center for growing citrus fruits, vegetables, and cotton. By 1915, the first shipment of grapefruits was sent from McAllen by rail. In the first half of the 20th century, the city's population grew significantly, driven in part by a large number of settlers of Mexican descent. This laid the foundation for the formation of the city's rich cultural heritage, combining American and Mexican traditions.