[1] Ilagan had its beginnings as an encomienda of Don Hernández de Paz circa 1617.

The town was also founded as a mission of the Dominican priests called San Miguel de Bolo on April 21, 1619.

During that time, it was officially named as San Fernando de Ilagan.

On April 22, 2024, a fire started from the roof of the 300-year old church which destroyed most of its interior.

[5] In 2003, the episcopal seat of the Roman Catholic Diocese of Ilagan was transferred from the Saint Ferdinand Parish Church to a new Church in Barangay Upi, in the town of Gamu.