The archaeological exploration and excavation at the Mt. Kamhantik Archaeological Site, led by Dr. Eusebio Z. Dizon from the
National Museum of the Philippines, revealed that Mulanay was inhabited by an organized Austronesian-speaking community from 500 to 1300 AD, descended from
Austronesians who migrated from
Taiwan. Carbon dating of teeth from burial No. 5 at the site revealed a date of 890 AD, while artifacts from a 2015 excavation included Neolithic stone tools and pottery similar to early Huynh-Kalanay styles from Taiwan and
Vietnam, dating between 1000 BCE and 200 AD. Ceramics from the
Sung Dynasty (960-1279 AD) were also discovered. These findings suggest that the ancestors from Mt. Kamhantik participated in trade networks between 500 and 1300 AD. The evangelization of Mulanay by the
Franciscan Missionaries was in 1600, while its civil foundation as a municipality was effected in 1745 through the approval of the King of Spain. During the Spanish regime, Mulanay was composed of the municipal territories of what is now
San Narciso,
San Francisco,
Catanauan and
San Andres, which was as big as the province of
Bataan. In 1755, Catanauan became a separate municipality followed by other remaining municipalities. Mulanay's territorial jurisdiction was reduced to . The original town of Mulanay composed of six (6) barangays was raided by the Moro pirates that led the town's executive together with the barangay heads to transfer the town site to the so-called Mayordomo, a sitio of Barangay Latangan. After several years, raids along coastal areas were lessened. The people returned to the town site, however, few barangay heads disagreed and left for Bantuin, Marinduque and Mindoro. In 1938, barrios Bondo, Cawayan, Inabuan, Ilayang Tayuman, Ibabang Tayuman, Kasay, Mañongon, Pagsangahan, and Silongin were separated from Mulanay to form the newly established municipality of
Bondo (present-day San Francisco). Based on the Philippine Statistics Authority Census Calendar Year 2010, it has a population of 50,826. The first town head of Mulanay during the Spanish Regime was Alcalde Mayor Eustaquio Manlangit, while the first town mayor during the American Occupation was Mayor Atanacio Ojeda. ==Geography==