Calatagan is a second class municipality located in the southernwestmost part of the Province of Batangas. It is approximately 125 kilometers southeast of Manila and 93 kilometers west of Batangas City. On the north it is bounded by the municipalities of Lian and Balayan, on the south by the Verde Island Passage, on the east by the Pagapas Bay and Balayan Bays, and on the west, by the South China Sea.
The word “Calatagan” is a derivative of the Tagalog word “latag” and is synonymous to “Kapatagan”. It means a vast portion of land lying between the hills and mountains. Thus, Calatagan means a large expanse of wide plain lands.
The land occupied by the municipality of Calatagan was acquired by Don Domingo Roxas from the Spanish Crown in 1829 and was called Hacienda de Calatagan. The successors of Don Pedro Roxas continued to develop it and by the first decade of the century it had progressed sufficiently to become a municipality in 1912, by virtue of Executive Order No. 78 by then GOVERNOR GENERAL WILLIAM CAMERON FORBES, Calatagan became a Municipality independent from its mother municipality, Balayan.