Myths recalling how islands were “fished up” or “thrown down” by (demi)gods are widespread in the Pacific Islands. Fishing-up myths are more numerous and are concentrated in a heartland comprising parts of Samoa, Tonga, the southern Cook Islands, and the Society Islands of French Polynesia. Geological details in many fishing-up myths suggest these recall the activities of shallow submarine (jack-in-the-box) volcanoes, notably in Tonga, and that these myths diffused to places where such volcanoes do not exist. Other fishing-up myths—particularly those recalling rapid emergence and/or successive uplift events and tectonic instability during the process of fishing-up—are suggested as recalling coseismic-uplift events (uplift coincident with large earthquakes), which are comparatively common in islands along the convergent plate boundaries of the southwest Pacific (including parts of Tonga and New Zealand). Throwing-down myths are less common in the Pacific, being effectively confined to places (near) where volcanoes erupted within the period of human occupation. Throwing-down myths are interpreted as recalling volcanic eruptions.