It includes Dimmit, Jim Hogg, La Salle, Maverick, Webb, Zapata, and Zavala Counties.

Five years after the founding of San Agustin de Laredo in 1755, its residents petitioned the Diocese of Guadalajara to provide them with a mission.

[2] In March 2016, Tamayo halted the construction of a Catholic student center at Texas A&M International University (TAMIU) in Laredo.

Tamayo did not attend the groundbreaking; nor did he offer an explanation for his opposition to the project, even to TAMIU President Ray Keck.

[9] Glen S. Jackson of Alexandria questioned Tamayo's opposition to the student center, which he said has caused a "hostile atmosphere" in the Laredo diocese.

[10] Meanwhile, Father Robert L. Kincl, a former judicial vicar for the diocese, announced that he would mail thirty letters opposing Tamayo's position to the Vatican.

In 2002, Reverend Cyriacus Udegbulem, a Nigerian priest serving in the Diocese of Brooklyn, was arrested in Laredo on a New York warrant for rape.

However, Udegbulem showed up in Laredo in March 2000, working as a hospital chaplain and occasionally celebrating mass.

[13] In February 2019, Bishop Tamayo announced that there had been no accusations from the Laredo area against diocesan priests since the founding of the diocese in 2000.