Morong was originally known as “Bayandati”, believed to the settlement located in Nagbalayong. Due to the scarcity of land available for cultivation, residents migrated to adjacent areas where wider lands can be found.
When the Spaniards arrived to this place in 1578 the residents were elusive and distant to newcomers. The Spaniards observed that people called “Moros’ engaged in trade with the residents, hence this place was called Moron.
Moron together with Bagac of Bataan up to Maragondon in Cavite became part of the Corrigimento de Mariveles that was administered by the Franciscan friars. Pampanga annexed the remaining towns of Bataan, which were then under the administration of the Dominicans. Later in 1674, Governor General Manuel Arandia annexed Moron and eleven other municipalities under the province of Bataan.
On June 10, 1955, Moron was renamed Morong by Bataan representative Jose R. Nuguid by virtue of Republic Act No. 1249 which was enacted by the Batasan Pambansa. The move was made because the municipality’s former name was thought to mean “immature or “unintelligent” person.