The Parish of Sto. Rosario was established in 1776. It was administered y the Augustinian Recollects.

The original church building was of native materials, later on reconstructed using permanent materials.

The first settlers were from a part of Lobo who were forced to move to this place due to the incurssion of pirates. The town was first called "Rosario" for the people were praying the rosary while fleeing from the marauders.

During the Philippine-American War (1899-1902) the church building and the town were burned by the revolutionists. The place became deserted and thus was called "Lumang Bayan" due to the transfer of the seat of governemnt to the present Rosario.

The church administration was transferred to the Oblates of St. Joseph in 1928. During, the Second World War, Rev. Fr. Antonio Fanchini, OSJ was brutally murdered by the Japanese soldiers on February 14, 1945. The church was also not spared and was destroyed during the liberation of the Philippines in 1945. Restorations were done and was finished by 1949 with the belfry of the original church preserved.

The parish is composed of the following barangays: Banaba, Banay-banay, Bawi, Bucal, Castillo, Cawongan, Manggas, Maugat Balimbing, Maugat West, Pansol, Payapa, Poblacio, Quilo-quilo North, Quilo-quilo South, San Felipe, San Migele, Tamak and Tangob.