It is dedicated to Saint Augustine of Hippo and is the episcopal seat of the Diocese of Iba which covers Zambales and Olongapo.

[1] In the early decades of Spanish colonization, the territory of Zambales included parts of present-day Pangasinan and Bataan.

[3] Opposition and conflicts with the local Aetas prompted the Recollects to build a fort in an area called Playa Honda which served as a refuge for the new converts.

Iba, also spelled as "Yba" and formerly named as "Paynawen", was eventually founded in 1611 as a visita of Masinloc.

[7] The church was the venue of the session of the Second Philippine Commission under William Howard Taft which founded the province of Zambales on August 28, 1901.