The first Catholic mission in Texas, then part of the Spanish colony of New Spain, was San Francisco de los Tejas. It was founded by Franciscan Father Damián Massanet in 1690 in the Weches area. The priests left the mission after three years, then established a second mission, Nuestro Padre San Francisco de los Tejas. near present-day Alto in 1716.^[3]With the end of the Mexican War of Independence in 1821, Texas became part of the new nation of Mexico.

In 1839, three years after the founding of the Republic of Texas, Pope Gregory XVI erected the prefecture apostolic of Texas, largely covering the territory of the present State of Texas.^[4] By the 1840s, Catholic missionaries were visiting Clarksville and Nacogdoches. The prefecture was elevated to a vicariate apostolic in 1842, about three years before Texas became an American state. On May 4, 1847, Pope Pius IX elevated the vicariate into the Diocese of Galveston.^[4]Marshall received its first missionary visit in 1853. The Tyler area would remain part of several Texas dioceses for the next 139 years.

Immaculate Conception Parish, the first in Jefferson, was established in 1867.^[5]During the early 1870s, Theodore Buffard would travel from Galveston to North Texas to conduct services in hotels and private houses. Sacred Heart Church, the first in Texarkana, was dedicatedd in 1871.^[6] The first parish in Tyler was Immaculate Conception, founded in 1878 to serve Irish railway workers in the area.^[7] In 1880, St. Anthony's was established as a mission church in Longview, with its church constructed in 1884.^[8] The Benedictine Sisters in 1892 opened St. Joseph Academy in Tyler, the first formal Catholic in the present-day diocese.^[9]

The Sisters of Charity of the Incarnate Word from Houston in 1916 opened Michael Meagher Memorial Hospital in Texarcana. An Irish civil engineer, Meagher had died in 1909, leaving his $75,000 estate to the sisters to open a hospital in the city.^[10] Today the facility is known as CHRISTUS St. Michael Hospital.

A contingent of the Sisters of the Holy Family of Nazareth arrived in Tyler in 1937 to open Mother Frances Hospital. Today it is CHRISTUS Mother Frances Hospital.^[11]In 1945, a contingent of Dominican sisters moved from Farmington Hills, Michigan to Lufkin to set up the Monastery of the Infant Jesus.^[12]Pope John Paul II founded the Diocese of Tyler on December 12, 1986, and it was formally erected on February 24, 1987.^[3] The pope appointed Charles Herzig of the Diocese of Galveston-Houston as its first bishop. Herzig died in 1991.^[13]Immaculate Conception Church in Tyler was now designated as the Cathedral of the Immaculate Conception.^[7]

In 1992, John Paul II appointed Auxiliary Bishop Edmond Carmody of San Antonio as bishop of Tyler.^[14]During his tenure, Carmody oversaw the founding of many new parishes in the diocese.^[15]

The pope named Carmody as bishop of the Diocese of Corpus Christi in 2000.^[14]To replace Carmody, Auxiliary Bishop Álvaro Corrada del Río from the Archdiocese of Washington was named bishop of Tyler by John Paul II in 2001. Pope Benedict XVI appointed del Rio as bishop of the Diocese of Mayagüez in Puerto Rico in 2011.^[16]

Joseph Strickland of the Diocese of Dallas was named bishop of Tyler by Benedict XVI in 2011. Strickland was the first native East Texan to head the diocese.^[17]

In May 2023, Strickland posted online "I reject [Pope Francis's] program of undermining the Deposit of Faith".^[18] In June 2023, it was revealed that the Dicastery for Bishops in Rome had completed an apostolic visitation to the diocese. It had been conducted by Bishop Emeritus Gerald Kicanas and Bishop Dennis Sullivan. Visitations are frequently a prelude to disciplinary action by the Vatican against a bishop.^[19] After the apostolic visitation, several senior cardinals allegedly advised Francis to pressure on Strickland into resigning.

Pope Francis removed Strickland as bishop of Tyler in November 2023.^[20] Bishop Joe Vasquez of the Diocese of Austin was appointed as apostolic administrator of the diocese. In December 2024, Francis named Auxiliary Bishop Gregory Kelly of the Diocese of Dallas as the new bishop of Tyler.^[21] That same month, the Vatican sent a letter to the cathedral parish, order it to stop all celebrations of the Traditional Latin Mass.^[22]

The priest Gustavo Cuello was arrested in 1997 on charges of abusing a 13-year-old girl. The victim stated that Cuello attacked her multiple times over a period of six months. After posting bail and fleeing to his native Ecuador, Cuello was extradited in 2003 to the United States. At his trial, Cuello pleaded guilty and was sentenced to life in prison.^[23] The Vatican laicized him in 2006.^[24]

In February 2019, the diocese published the names of three priests associated with the diocese who had been credibly accused of sexually abusing minors. Only one of the three, Cuello, had allegations reported within the diocese.^[25]

• Bishop T. K. Gorman Catholic School – Tyler^[32]
• St. Mary's Catholic School – Longview^[33]
• St. Boniface Catholic High School – Nacogdoches^[34]