Due to the existence of small Roman Catholic (Latin) communities in Mersin and Tarsus and the increasing economic rise of the former fishing village of Mersin, a church had to be built as early as 1840. The impetus for building the church came from Maronites who had been expelled from Lebanon and who fled to Mersin after clashes with Muslims and Druze. On January 13, 1853, it was decided that a Catholic church should be built under the supervision of France. After May 1854, the Church and the Saint Anthony of Padua College (Padova'lı Saint Antuan Koleji) were opened by the Capuchins.
It was not until September 15, 1855 that Sultan Abdülmecit I gave permission to build a church with a ferman, but the ferman was not handed over to the church until 1891 due to bureaucratic difficulties. In 1867 the church received a harmonium, in 1874 a cemetery.
During World War I, Father Edmond was recalled to France and the church school had to be closed. After the war it was reopened. In May 1924, all religious schools in the country were closed, including those of the Church. In 1928, part of the church garden and the boys' school were expropriated by the state for the construction of a road, and the church cemetery was expropriated and nationalized. Since the Tarsus Catholic Church was closed in 1942, its church property was transferred to the Mersin Catholic Church.
In 1945 the Turkish state expropriated the Mersin Church girls' school and turned it into an orphanage, and in 1947 land was also confiscated for the construction of a railway. In 1951 the Capuchin monastery was attached to the orphanage. Since the death of the minister of the Maronite Church, the Maronites of Mersin have held their services in the Latin Catholic Church. In 1953 the sisters' convent of the church was converted into the Turkish "January 5th Elementary School" (5 Ocak İlkokulu), in 1956 another 1350 m² of land were expropriated for the construction of a Turkish school. In order to expand the school, another part of the church garden was confiscated in 1967.
In 1958 the church got a new altar and in 1975 the bell tower got a new clock. In 1990 the church was renovated. At the request of Pope John Paul II, the church became a cathedral in 1991, and Ruggero Franceschini resided there as the first bishop. In 1999 the bishopric was moved from Mersin to İskenderun.
Source: Wikipedia