The Archdiocese of Mobile encompasses 22,969 square miles with 76 parishes and seven missions and a total Catholic population of approximately 108,000.

It comprises the counties of Autauga, Baldwin, Barbour, Bullock, Butler, Choctaw, Clarke, Coffee, Conecuh, Covington, Crenshaw, Dale, Dallas, Elmore, Escambia, Geneva, Henry, Houston, Lee, Lowndes, Macon, Mobile, Monroe, Montgomery, Pike, Russell, Washington and Wilcox.

That next year, Henri Roulleaux De la Vente became the first resident priest in the new settlement, under the authority of the Diocese of Quebec.

[2] In 1793, the Vatican erected the Diocese of Louisiana and the Two Floridas centered in New Orleans to serve Catholics in the Spanish colonies.

At the time of his accession, Portier was the only clergyman in the vicariate; he had two churches in Florida and one in Mobile, with an estimated Catholic population of 6,000.

In 1829, Pope Pius VIII erected the Diocese of Mobile, taking the Florida Territory and the new State of Alabama from the vicariate.

[3] In 1830, Portier established Spring Hill College in Mobile, the first institution of higher learning in Alabama.

[7] That same year, Portier sent his priests into interiors part of Alabama to minister to small clusters of Catholics in the area.

[9] Portier brought the Brothers of the Sacred Heart from France to the diocese about 1847, and the Daughters of Charity from Emmitsburg, Maryland, to manage orphan asylums for boys and girls, respectively.

[3] In 1854, Know Nothing elements in Mobile forced the Daughters of Charity to leave the City Hospital, spreading false charges of mismanagement.

[3] In 1860, Quinlan traveled to Ireland, France and Rome, hoping to raise funds and recruit more priests for the diocese.

[12] The diocese was devastated by a major hurricane in 1906; many churches were either totally or partially destroyed, but were rebuilt or repaired under Allen's direction.

[12] Deeply concerned for the African American community, he invited the Josephite Fathers to direct the black missions in the diocese, founded St. Joseph's College in order to "educate young colored men to be catechists and teachers," and sanctioned the establishment of the Knights of Peter Claver.

Toolen opened several new churches, orphanages, hospitals, and other institutions that were meant to minister exclusively to African Americans, leading opponents to call him "the nigger bishop".

In 1957, Toolen invited Mother Mary Angelica and the Poor Clares of Perpetual Adoration to establish a religious community for African Americans in the diocese.

[17] In 1965, Toolen ordered the Society of Saint Edmund to remove Maurice Ouellet from his post as pastor in Selma.

[22] During his 10-year-long tenure in Mobile, May established eight parishes and two deaneries, dedicated twelve churches, founded two schools, and erected a convent.

[12] He also dedicated several other institutions, including parish centers, elderly homes, and a new wing and intensive-care unit at Providence Hospital.

[23] In 1993, David Trosch, an archdiocesan priest in Magnolia Springs, started advocating the theory of justifiable homicide as a justification for killing medical professionals providing abortion services to women.

[24] Trosch then attempted to place an advertisement in the Mobile Press-Register newspaper with a cartoon showing a man pointing a gun at a doctor holding a knife over a pregnant woman.

"[25] Lipscomb removed Trosch from his pastoral assignments in August 1993, allowing him to continue celebrating mass but banning him from any "...public persona in the Church".

[24] When Lipscomb retired in 2008, Pope Benedict XVI appointed Bishop Thomas Rodi of Biloxi that same years as the next archbishop of Mobile.

[27] In December 2018, Archbishop Rodi released the names of 29 priests and religious order clergy with credible accusations of sexual abuse of minors while serving in the Archdiocese of Mobile, dating back to 1950.

Vernon, was charged with lewd conduct towards a masseuse while receiving a massage on the Carnival Cruise ship Fantasy.

In July 2023, Alexander (Alex) Crow,[31] a 30-year-old priest of the archdiocese who had been ordained in 2021, abandoned his clerical duties and run away to Europe.

[34][35]It was reported to the government authority because Crow was accompanied by an 18-year-old girl who had just graduated from the McGill-Toolen Catholic High School.

[44] Michael Portier (1825–1859) Thomas Joseph Toolen (1954–1969), archbishop ad personam John Lawrence May (1969–1980), appointed Archbishop of Saint Louis Montgomery Catholic Preparatory School – Montgomery[45] These are independent schools within the territory but not under the administration of the Archdiocese of Mobile.