English: St. Ferdinand Parish Church (Proto-Cathedral of Ilagan): Ilagan City, Isabela

The present town of Ilagan was founded by Fr. Pedro Jimenez, OP as a town in 1678 and as a parish on May 4, 1686 under the patronage of San Fernando Rey (St. Ferdinand). He also founded the nearby mission pueblos of Itugud (Lenzon, Gamu, Isabela) and Gamu. Both of them share the civil and ecclesiastical foundation of Ilagan. During his missionary enterprise in Ilagan, Itugud and Gamu, Fr. Pedro Jimenez, OP introduced not only the Gospel of Christ but also the Gospel of Western civilization. He died in Itugud on December 20, 1690 due to fever which he got after soaking himself on the rain while plowing the field. He was buried in Itugud but his remains were transferred to Ilagan in 1700 and re-interred on the grounds of the present St. Ferdinand Parish Church, probably at the old Campo Santo beside the church.

The present foundations of Ilagan church was built by Fr. Miguel Matos, OP from 1696 to 1700 as a mamposteria and brick church. The belltower was constructed in 1777 by Fr. Pedro de San Pedro, OP and it was finished by Fr. Joaquin Sancho, OP in 1783. On December 20, 1803, the church became the final resting place of Nueva Segovia Bishop Agustin Pedro Blaquer, OSA who died in Ilagan on December 19, 1803 after he got sick during his visit to Cauayan. He was interred at the Epistle side of the church (see Malumbres, "Historia de Cagayan", 104-05). The sacristy of ladrillo was constructed in 1829 by Fr. Luis Garcia, OP. The church was destroyed by a typhoon in 1866 and Fr. Pablo Almazan, OP demolished major portions of the church in order to build a bigger one. However, the result was neither a big one or a small one (see Malumbres, "Historia de la Isabela", 582). In 1892, Fr. Isidro Martinena, OP established a campo santo outside of Ilagan poblacion which is located in Barangay Santo Tomas. The ladrillo fence of the campo santo could still be recognized. The present façade and major parts of the church were constructed in the 1930s. It was renovated in the 1960s. The church became the seat of the Diocese of Ilagan in 1973 until 2003 when it was transferred to the present Cathedral in Barangay Upi, Gamu, Isabela. In 2013, the present Cathedral was placed under the patronage of St. Michael the Archangel. Despite the transfer, both city and diocese still remain under the patronage of Saint Ferdinand.

As for the Old Saint Ferdinand Cathedral, it returned to its status as the parish church of Ilagan City. The belltower, sanctuary, sacristy, parish hall and the old campo santo are the remaining traces of the Spanish-era church of Ilagan. The ladrillo details of the sanctuary, the Epistle side and Gospel side of the church were once again revealed after the cement were chipped-off during a recent renovation.