The founding decree of the College of Guadalupe, dated 1704, mentions that the apostolic work was mainly directed toward the province of Coahuila and also to the lands of Texas. Typically, around 30 religious men lived at the College, and the friars who went out to evangelize had to spend at least two years preparing within this institution.

The first missions were led by Friar Antonio Margil de Jesús along the banks of the Sabinas River in Coahuila, but the hostility of the indigenous people prevented them from thriving. Nevertheless, the friars' determination was not deterred. By 1716, they had established some missions along the San Antonio and Guadalupe rivers in Texas and even managed to reach the borders of French Louisiana. By the late 18th century, they had also founded over 14 towns in the Mexican Gulf Coast region (present-day Tamaulipas), took charge of 15 missions left by the Jesuits in the Sierra Tarahumara, and reached Alta California. Thus, the work of the missionaries of Guadalupe is reflected in more than thirty mission foundations, covering much of the northern frontier during the colonial period.