Tanay was settled by early Austronesian people. Shortly after the conquest and subjugation of Manila by the Spaniards and the surrounding lake areas by Juan de Salcedo in 1570-1574, Franciscan missionaries arrived to Christianize the inhabitants of what is now the Morong-Pililla area. In 1583, both Morong and Pililla were created as separate towns with Tanay forming part of Pililla.