The Diocese of Gallup (Latin: Dioecesis Gallupiensis, Spanish: Diócesis de Gallup) is a Latin Church ecclesiastical territory, or diocese, of the Catholic Church in northwestern New Mexico and northeastern Arizona in the United States. It is a suffragan diocese in the ecclesiastical province of the metropolitan Archdiocese of Santa Fe.

The mother church of the Diocese of Gallup is the Sacred Heart Cathedral in Gallup, New Mexico. As of 2023, the bishop of Gallup is James Sean Wall.

The Diocese of Gallup comprise the following counties:

• All of Navajo and Apache counties in Arizona
• All of San Juan, McKinley, Cibola and Catron counties in New Mexico
• Parts of Rio Arriba, Sandoval, Bernalillo, and Valencia counties in New Mexico

The current Diocese of Gallup has undergone several name changes since its territory became part of the United States.

The New Mexico counties came from:

1. Vicariate Apostolic of New Mexico (1850 to 1853)
2. Diocese of Santa Fe (1853 to 1875)
3. Archdiocese of Santa Fe (1875 to 1939)
4. Diocese of Gallup (1939 to present)

The Arizona counties came from:

1. Diocese of Santa Fe (1868 to 1891)
2. Vicariate Apostolic of Arizona (1891 to 1897)
3. Diocese of Tucson (1897 to 1939)
4. Diocese of Gallup (1939 to present)

The first Catholic missionaries to the Navaho Nation were Franciscan priests who arrived there in 1898. The first Catholic church in Gallup, New Mexico, was Sacred Heart Church, constructed by Reverend George Julliard in 1899. St. Michael Indian School was opened in 1902 in St. Michael's, Arizona by Franciscans from St. Michael's Mission in Window Rock, Arizona, with financial assistance from Katharine Drexel.

Pope Pius XII erected the Diocese of Gallup on December 16, 1939, taking its territory from the Archdiocese of Santa Fe and the Diocese of Tucson. The pope named Reverend Bernard T. Espelage as the first bishop of Gallup.

During Espelage's 29-year tenure, the Catholic population of the diocese increased from 30,000 to 79,260. The number of priests went from 32 to 108 and the number of parishes from 17 to 53. Espelage retired in 1969. That same year, the Vatican erected the Diocese of Phoenix, taking part of its territory from the Diocese of Gallup.

The second bishop of Gallup was Bishop Jerome J. Hastrich from the Diocese of Madison, named by Pope Paul VI in 1969. Pope John Paul II named Reverend Donald Pelotte as coadjutor archbishop in 1986 to assist Hastrich. When Hastrich retired in 1990, Pelotte automatically succeeded him as bishop of Gallup. Pelotte was the first Native American Catholic bishop in the United States, an Abenaki from Maine.

In 2007, Pelotte suffered a traumatic brain injury at his home and was hospitalized at his home. In January 2008, Pope Benedict XVI named an apostolic administrator to run the diocese while Pelotte recovered. In April 2008, Pelotte retired due to his health problems. The pope in 2009 named Monsignor James S. Wall from the Diocese of Phoenix to replace Wall as bishop of Gallup.

In 2013, Wall renovated a chapel used by local seminarians with sacred art in santero, a New Mexico folk art based on Spanish colonial art. Artist Arlene Sena said that prayer was "the key to this tradition". The chapel contains images of the Holy Family, James, brother of Jesus, Francis de Sales, Our Lady of Mount Carmel, two angels, and the Sacred Heart. In May 2023, Wall announced that the diocese was taking over operation of St. Michael's Mission from the Franciscans due to their inability to support it any longer. Also in 2013, the diocese filed for Chapter 11 bankruptcy in order to settle the sexual abuse lawsuits against diocesan clergy.

As of 2023, Wall is the current bishop of the Diocese of Gallup.

In 2004, James Burns was sentenced to 18 months in prison for sexually abusing a boy in Blanco, New Mexico. It was later estimated that Burns had molested several dozen boys during his career as a priest. The diocese in 2005 identified Reverend Clement A. Hageman as an abuser of children from the 1940s to the 1970s. Hageman was transferred to the Archdiocese of Santa Fe from the Diocese of Corpus Christi when allegations of sexual abuse arose there. The archdiocese later moved Hageman for the same reason to the Diocese of Gallup.

In 2011, several men from sued the diocese, claiming that they had been sexually abused by Hageman. They accused the church of dumping Hageman in poor parishes in the diocese to avoid scandal elsewhere. In 1940, Bishop Espelage had asked Archbishop Rudolph Gerken of Santa Fe for his opinion of Hageman. Gerken replied that Hageman “was guilty of playing with boys.” One victim reported that Hageman would bring a boy in from the playground to his office and then assault him.

The diocese released a list of 42 clergy and one teacher with credible accusations of sexual abuse of minors in 2014.

In February 2017, it was announced that the diocese had paid more than $17.6 million to 57 victims of sexual by diocesan clergy, clearing the way for the diocese to leave bankruptcy.

1. Bernard T. Espelage (1940–1969)
2. Jerome J. Hastrich (1969–1990)
3. Donald Edmond Pelotte (1990–2008)
4. James Sean Wall (2009–present)

• Donald Edmond Pelotte (1986–1990)

Schools with high school divisions

• St. Michael Indian School (K-12) – St. Michaels, Arizona

Schools with former high school divisions

• Gallup Catholic School – Gallup, New Mexico (high school closed in 2013)
• St. Bonaventure School – Thoreau, New Mexico (high school closed in 2001)

Coat of arms of Roman Catholic Diocese of Gallup

Notes Arms was designed and adopted when the diocese was erected Adopted 1939 Escutcheon The arms of the diocese are a green field with three red crosses below a silver star. Symbolism The green field honors the heritage of the Native American peoples in the diocese. The crosses represent Reverends Francisco Letrado, Martin de Arvide, and Pedro de Avila y Ayala, all of whom were martyred. The star represents Mary, mother of Jesus, the patroness of the diocese.

• Roman Catholic Diocese of Phoenix
• Roman Catholic Diocese of Tucson

• Roman Catholic Diocese of Gallup official site
• Arizona Catholic Conference

35°31′25″N 108°44′03″W / 35.52361°N 108.73417°W / 35.52361; -108.73417