But in the book Atlas de Filipinas by José María Algué, SJ - a Spanish-Roman Catholic priest and meteorologist in the observatory of Manila published in 1899 (In 1900 published in English: Atlas of the Philippine Islands by the United States Coast and Geodetic Survey, now the U.S. National Geodetic Survey); Pinabacdao was cited as Pinabágdao and listed as a pueblo or town in the former island province of Samar.

Due to lack of official and authenticated historical accounts pertaining to the origin of the town's name, the municipal government is only relying on folktales which were handed from prominent ancestors to their eager descendants.

Folktales revealed that the town of Pinabacdao got its present name by the time when the Philippines was still under the Spanish colonial era; the provincial governor of Samar asked Capitan Doquerez (believed to be the founder and first mayor of Pinabacdao) as to what punishment he would impose to those who violated any rule or law.

Doquerez insisted that he will not impose fines and imprisonment, instead they will be punished by asking them to "bakdaw" or stand on an ant colony.

[citation needed] Another folktale or legend surrounding the town suggests that Pinabacdao's name was derived from miscommunication.

These was the time when according to the folktale during the early years of settlement, officers from the Samar provincial government (probably on a mapping, census or exploratory survey) passed along the newly organized town and saw a man tied on a pole, standing on an ant colony.

02 series of 1946 issued by President Manuel A. Roxas, and separated from Calbiga as a reestablished municipality on July 16, 1946.

Pinabacdao lies at the southwest central coast of Samar Island and crossed along by the Pan-Philippine Highway.

The East district is composed of barangays situated in high altitude areas or those located in the eastern part of the municipality.