Atimonan  ', officially the ' (), is a in the province of , . According to the , it has a population of people. It lies on the eastern shore of the province, southeast of Manila. Atimonan is bounded by the municipalities of Gumaca, Plaridel, Pagbilao and Padre Burgos. Atimonan is politically subdivided into 42 barangays. There were conflicting stories on how Atimonan got its name. Some concluded that the name Atimonan originated from a tree known as "Atimon" alleged to have been prevalent in the area and had reportedly served many uses to the residents. These trees are now extinct and its non-existence could not be accounted for. Others say it came from the words "atin muna", signifying a policy, unity of feeling and sentiments among the residents that bolster their spirit in the fight against their enemies during that time. But the most popular version is that it originated from the name of its founder, Simeona Mangaba, known to her town mates as "Ate Monang". She is a woman reputed to be of unquestionable leadership, which the people regarded as their adopted parent, leader and protector. Ate Monang was the eldest sister of Francisco Mangaba, the first captain of the town. She founded the town on February 4, 1608 along the banks of the big Maling River, now known as Atimonan River. Living along the river bank, the people has always been a prey to Moro attacks and so for fear of Moro reprisals, the inhabitants decided to transfer to "Palsabangon", now a barrio of Pagbilao, Quezon. However, the people felt discontented in Palsabangon because the place abounds in wild crocodiles that from time to time disturbed them. So, after two years of stay (1610), they left the place and transferred to "Babyaw", a part of Atimonan. They settled in Babyaw for almost 14 years, but transferred again to another site called "Minanukan" for some unknown reasons. In 1635, they again transferred to another place called "Bisita", but some families separated from the majority and settled in "Yawe", now San Isidro, a barrio in Padre Burgos, Quezon. The next year, when Simeona Mangaba learned of what happened to the original group of settlers, she, together with Fray Geronimo de Jesus, a Spanish friar, tried to unite them once more and convinced them to return to the place where it was first founded.