Holocene sea-level changes affected people living in the Pacific Islands and their ancestors along the western Pacific Rim. Sea-level changes, particularly those that were rapid, may have led to profound and enduring societal/lifestyle changes. Examples are given of (1) how a rapid sea-level rise (CRE-3) about 7600 BP could ultimately have led to the earliest significant cross-ocean movements of people from the western Pacific Rim into the islands; (2) how mid to late Holocene sea-level changes gradually created coastal environments on Pacific Islands that were highly attractive to human settlers; (3) a hypothesis that rapid sea-level fall during the ‘AD 1300 Event' brought about widespread disruption to trajectories of cultural evolution throughout the Pacific Islands; and (4) the effects of recent and likely future sea-level rise on Pacific Island peoples.