Long time ago during the spanish regime located in the western part of amulung is a place called “kabakbakiran” which means forest. Aside from wild animals there where only few inhabitants living in the place headed by oldest of them all which they obey, request and believe. One morning a spanish traveler happened to reach the place. On his wayhe met an old man cutting a shrub. He tried to ask how they called the place (speaking in spanish language). The man holding the shrub answer “balbalauini” believing that the stranger was asking what he is holding.
As the time went on, the place was turned into farmland and the name babalauini was carried on until such time the barangay is to be registered. The head of the cabeza de barangay registered the place “balauini” instead of balbalauini for it is shorter and easier to pronounce. Because of the continious erosion of the cagayan river the inhabitants of balauini transferred to the sitio which they call it kamanggaan because there are several mango trees living/growing in this place.
The barangay officials made a resolution to change the name of kamanggaan to san juan in honor of hon. Juan ponce enrile and juan malamug because they were a contributor to the success of this barangay.