The Diocese of San Bernardino (Latin: Dioecesis Sancti Bernardi, Spanish: Diócesis de San Bernardino) is a Latin Church ecclesiastical territory, or diocese, in Southern California in the United States. Erected by Pope Paul VI on July 14, 1978, its jurisdiction extends over San Bernardino and Riverside counties. As of 2021, the diocese had 92 parishes and 12 missions in its territory. Its cathedral is Our Lady of the Rosary Cathedral in San Bernardino.

The Diocese of San Bernardino is a suffragan diocese in the ecclesiastical province of the metropolitan Archdiocese of Los Angeles.

In 2019, the Diocese of San Bernardino reported a population of 1,740,655 Catholics, a 22,000 increase from the previous year. That made San Bernardino the fifth largest Catholic diocese in the United States. The main cause of this increase was thought to be the increasing migration of Hispanics to the area in part due to the economic opportunities and affordable housing in comparison to the rest of California.

During the 18th century, the San Bernardino and Riverside areas were part of the province of Las Californias in the Spanish colony of New Spain. In 1804, the Spanish split the Province of California into two territories:

• Alta California (Upper California), including the modern American states of California, Nevada, Arizona, and Utah, along with western Colorado and southwestern Wyoming
• Baja California Territory (Lower California), including the modern Mexican states of Baja California and Baja California Sur

Spanish missionaries from the Mission San Gabriel Arcángel in present-day Los Angeles established the first church in the San Bernardino area in 1810 at the village of Wa'aachnga, later Politania, between what is now San Bernardino and Colton. Reverend Francisco Dumetz named the church San Bernardino after the feast day of St. Bernardino of Siena. The Franciscans also named the San Bernardino Mountains.

The first European settlement in present-day Riverside County was an estancia, or farmer, established by the Mission San Luis Rey de Francia at the Luiseño village of Temescal. In 1819, Franciscan missionaries established the San Bernardino de Sena Estancia in what is today Redlands.

After the Mexican War of Independence ended in 1821, Alta California became part of Mexico. The Mexican Government in 1835 secularized all the Catholic missions in Alta California, including the Mission San Luis Rey de Francia.

In 1840, Pope Gregory XVI set up the Diocese of California. The new diocese included both Alta California and Baja California. Gregory XVI set the episcopal see at present-day San Diego in Alta California. The first bishop of the new diocese was Francisco Garcia Diego y Moreno. Moreno designated the Mission Santa Barbara in Santa Barbara as his pro-cathedral.

After ceding Alta California to the United States at the close of the Mexican–American War in 1848, the government of Mexico objected to San Diego, a see city now located in the United States, having jurisdiction over Mexican parishes. In response, the Vatican divided the Diocese of California into American and Mexican sections in 1849. The American section became the Diocese of Monterey; the see city was moved to Monterey because of its more central location. The Royal Presidio Chapel in Monterey became the cathedral of the new American diocese.

In 1859, Pius IX renamed the Diocese of Monterey as the Diocese of Monterey-Los Angeles to recognize the growth of Los Angeles; the see was transferred to Los Angeles in 1876. St. Francis de Sales, the first parish in Riverside County, was established in 1886.

In 1922, the Vatican divided the diocese again, with the southern portion becoming the Diocese of Los Angeles-San Diego. The Diocese of San Diego was erected in 1936, including San Bernardino and Riverside Counties. These two counties would remain part of the Diocese of San Diego for the next 42 years.

Pope John Paul II erected the Diocese of San Bernardino on November 6, 1978, taking San Bernardino and Riverside Counties from the Diocese of San Diego. He appointed Reverend Phillip Straling of San Diego as the first bishop of San Bernardino.

During Straling's episcopate, the diocese grew from about 235,000 people to 800,000, and from 85 parishes to 105. For the formation for ministry, he established a diaconate program, and started the Straling Institute in 1980 for laymen. In 1995, John Paul II named Straling as bishop of the Diocese of Reno and replaced him in San Bernardino with Auxiliary Bishop Gerald Barnes.

Under Barnes, the diocese operated three high schools, twenty-three elementary schools and three pre-schools. In 2001, Barnes inaugurated the Annual Bishop's Golf Classic to fund scholarships to families who are unable to afford a Catholic education for their children. During his tenure, Barnes closed four primary schools in the California communities of Barstow, Banning, Apple Valley and San Bernardino. The high desert portion of the diocese currently has no Catholic schools.In 2019, Auxiliary Bishop Alberto Rojas of the Archdiocese of Chicago was appointed as coadjutor bishop of the Diocese of San Bernardino by Pope Francis to assist Barnes.

When Barnes retired in 2020, Rojas automatically succeeded him as bishop. In May 2023 seven priests were ordained for San Bernardino, the largest number of ordinations in the diocese's history. As of 2023, the current bishop of San Bernardino is Alberto Rojas.

Former Monsignor Patrick O'Keefe was charged in August 2002 with 15 felony counts of oral copulation with a minor. Then serving in the Diocese of San Diego, O'Keefe fled to Ireland and was never arrested. The alleged victim, then a 17 year old girl, said she was abused by O'Keefe in 1972. She reported the abuse to the diocese in 1989, but it did nothing. The diocese finally removed O'Keefe from ministry in 1994 after receiving abuse reports from other women; at that time, the diocese reached a settlement with one of his victims. In July 2003, a US Supreme Court ruling on a California law forced prosecutors to drop the O'Keefe case.

In April 2003, the Diocese of San Bernardino sued the Archdiocese of Boston. The diocese charged that the archdiocese gave them false information on Paul R. Shanley, a priest who transferred to San Bernardino from Boston in 1990. The archdiocese had sent Shanley to California to recover from various ailments and practices ministry part time. Despite Shanley having a record of sexual abuse of minors in Massachusetts, the archdiocese described him to the diocese as "a priest in good standing". In 1990, Shanley was accused of abusing a male teenager at Cabana Club Resort, a gay-oriented hotel that Shanley and another priest owned in Palm Springs. In 2002, Shanley was extradited from California to Massachusetts to face sexual assault charges there. In July 2003, after speaking to the new archbishop of Boston, Sean O'Malley, Barnes decided to drop the lawsuit.

Reverend Joseph Jablonski, a visiting priest with the Missionaries of the Sacred Heart, was removed from ministry in the diocese in 2014. The diocese had received a complaint that Jablonski had been grooming a young man for a possible sexual encounter. His order sent Jablonski to treatment, then assigned him again to ministry. Jablonski worked in three Illinois dioceses until 2018, when his name appeared on the San Bernardino list of credibly accused priests.

Reverend Marcelo De Jesumaria of Arrowhead was convicted in May 2015 of sexually abusing a female passenger during an August 2014 flight from Philadelphia to Los Angeles. After waking from a nap, the victim realized that De Jesumaria was groping her breast and groin. He was arrested after the plane arrived in Los Angeles. In August 2015, he was sentenced to six months in prison and six months of home detention. De Jesumaria was immediately suspended from ministry after his arrest.

In 2018, the diocese released a list of 34 priests with credible accusations of sexual abuse of minors since the founding of the diocese in 1978. The diocese announced in May 2019 its participation with other Southern California dioceses in a voluntary compensation plan for victims of sexual abuse by clergy.

Nick Flores in December 2019 sued the diocese, claimed that he had been sexually abused by Reverend Louis Perreault at Our Lady of the Valley Church in Hemet in the 1990s. His attorneys accused the diocese of having been a so-called dumping ground for sexually abusive priests. The diocese had permanently removes Perreault from ministry in September 2011 after receiving abuse allegations against him.

1. Phillip Francis Straling (1978–1995), appointed Bishop of Reno
2. Gerald Richard Barnes (1995–2020)
3. Alberto Rojas (2020–present)

Alberto Rojas (2019–2020)

• Gerald Richard Barnes (1992–1995)
• Dennis Patrick O'Neil (2001–2003)
• Rutilio del Riego Jáñez (2005–2015)

• Aquinas High School – San Bernardino
• Notre Dame High School – Riverside
• Xavier College Preparatory High School – Palm Desert

Our Lady of the Desert School in Yucca Valley is not associated with the diocese, though it offers traditional Catholic education.

• Catholic Church by country
• Catholic Church hierarchy
• List of the Catholic dioceses of the United States

• Official website

34°07′46″N 117°17′35″W / 34.1294°N 117.2930°W / 34.1294; -117.2930