The Church of the Sacred Heart traces its origins to 1887, when it was founded as a satellite mission of the Sacred Heart parish in Tombstone. Early services were held in a small adobe hall built by Father Dolge and supported by missionaries such as Fathers Granjon and Freri. As Nogales grew into a major border crossing and trade center in the late 1800s, Sacred Heart became increasingly important. In 1897, the parish center was transferred from Tombstone to Nogales under Father Julius Gheldof, who built a new church to serve the rapidly expanding Catholic population. A major turning point came with the arrival of Father Louis Duval in 1905, a French missionary whose leadership fundamentally shaped Catholic life in Nogales. He invited the Sisters of Mercy to establish St. Joseph’s Hospital, then founded a parochial school in 1910, strengthening the church’s educational and charitable role. During the 1920s, anticlerical persecution in Mexico, especially during the Cristero War, drove thousands of Mexican Catholics across the border to attend Mass. Sacred Heart became a spiritual refuge for these displaced worshipers. The overwhelming increase in attendance pushed Father Duval to launch an ambitious expansion project beginning in 1928, drawing construction resources from across Arizona and Sonora. The enlarged Sacred Heart Church was completed during the early 1930s and served a binational congregation throughout a time of social, economic, and political upheaval. After years of fundraising, the church was officially consecrated in 1946 upon full repayment of its construction debts—a remarkable achievement given the Depression and World War II. Monsignor Duval, whose vision and leadership drove the parish’s transformation from a small frontier mission into a major religious institution, served until ill health forced his retirement. He died in 1947, honored by thousands who regarded him as a foundational figure in the spiritual and civic life of Nogales.