John Anthony Forest, third Catholic bishop of San Antonio, son of Jean and Marie (Thollet) Forest, was born at St. Martin-la-Sauvete, Loire, France, on December 26, 1838. He was educated at the Petit seminaries of St. Jodard, Loire, and L'Argentière, Rhône, and at the Grande Seminary of St. Irénée, Lyons. He was subdeacon at Lyons when he responded to the call issued by the newly consecrated Bishop Claude Marie Dubuis of Galveston for seminarians to come to Texas as missionaries. Forest and about fifty of his fellow students sailed for New Orleans on January 3, 1863. They were refused admittance to the port when they arrived, however, since Gen. Ben Butler suspected that they might be allies of the Confederacy. He finally allowed them ashore when he had been convinced that they were only missionaries. They entered the seminary at Bouligny, New Orleans, where Forest was ordained by Bishop Dubuis on April 17, 1863. Shortly thereafter, he and two companions were sent to San Antonio, Texas, to begin their apostolates. They traveled on foot and by oxcart by way of Mexico because of the raging Civil War and arrived at their destination about three weeks later. Forest stayed in San Antonio only a month before he was assigned to work as assistant to Father Charles Padey, pastor of St. Mary's Church at Smothers Creek in Lavaca County. He eventually became pastor of St. Mary's and later of Sacred Heart Church in Hallettsville, which was about four miles away. During his thirty-two years in that area, he built many new churches and schools and made improvements in many others. He did much of the labor required for these tasks with his own hands. When he arrived at St. Mary's he knew little English and no Czech. Within three months he had mastered a practical vocabulary in both languages and had won the admiration of his parishioners.
Forest remained in Hallettsville until 1895, when he was appointed successor to Bishop John C. Neraz of San Antonio. He was consecrated on October 28 of that year in San Fernando de Béxar Cathedral by Archbishop Francis Janssens of New Orleans. His tenure as bishop, like that of Neraz, was marked by tremendous growth of the diocese. Many new parishes came into being, and many of the old ones built larger churches and schools. The religious orders in the area were also establishing new convents and schools. During Forest's first year as bishop, the Sisters of Divine Providence opened the Academy of Our Lady of the Lake (now Our Lady of the Lake University). In the years that followed, the Sisters of Charity of the Incarnate Word opened Incarnate Word Academy, and the Sisters of Our Lady of Charity of Refuge came to San Antonio at the request of the bishop and founded Our Lady of Victory School, a rehabilitation center for delinquent and neglected girls. In 1899 the Ursuline Sisters, who had been in the city since 1851, established a new academy; and in 1902 Forest invited the Claretians to take charge of San Fernando Cathedral to work with the Spanish-speaking population.
He continued to bring in religious orders and to develop the educational facilities in the diocese. Though this work was important, it was something of an outgrowth of the work of previous bishops. Forest's most striking achievement was his fostering of the establishment of more and better charitable institutions. The Incarnate Word nuns bought St. Mary's Sanatorium in Boerne in 1896 to work exclusively with tubercular patients, and Forest established the Home for the Colored Poor in San Antonio in 1901. He put Father John A. Dumoulin in charge of the home, which became the nucleus of Holy Redeemer Parish, associated with St. Peter Claver Parish. In 1906 St. Francis Home for the Aged was completed, and in 1910 the doors of St. John's Sanitarium (named for Forest) in San Angelo were opened.
Forest continued his building projects, but as the Catholic population grew, he also sought to improve the administration of the diocese. He expanded the number of officials from about four to about eighteen in the sixteen years he held office, and in 1906 he called the first diocesan synod at St. Louis College (now St. Mary's University). Also during his tenure San Antonio was honored by the visits of two apostolic delegates to the United States. The first delegate, Francesco Cardinal Satolli, visited on February 24, 1896, and in 1903 Archbishop Diomede Falconio came to San Antonio to bless the cornerstone of the new Oblate Seminary (now the Oblate School of Theology).
Forest's health began to fail around 1910, and he asked for an assistant to help with the affairs of the diocese. Father John William Shaw of Mobile, Alabama, was appointed coadjutor with the right of succession on February 7, 1910. The bishop formally welcomed him in a ceremony held at San Fernando Cathedral on May 18 and shortly thereafter retired to Santa Rosa Infirmary (now Santa Rosa Hospital). He suffered a stroke in February and died on March 11, 1911, thus ending an era in the history of the Catholic Church in Texas. Forest was the last of the great missionaries, the "Apostles from Lyons," who came to evangelize the Southwest. Bishop Shaw and Bishop John B. Morris of Little Rock, Arkansas, celebrated a pontifical Mass for him on March 15, 1911, in San Fernando Cathedral. Forest was buried in San Fernando Cemetery.