Goliaths have learned to adapt to the natural hurricane cycle on the island of Korujo. Because of its close proximity to the Hurricane Belt, Korujo is completely wiped out every 150 years or so. Nomadic goliath tribes settle in other parts of the world while that happens and then return to the island to extract the massive wealth from all of the previous civilizations that have attempted to make a permanent home on Korujo.
In modern days, the tribes function more like excavation companies. Due to a disagreement about how to handle preservation of historical artifacts, a line was drawn across the island and agreement was made that in West Korujo, excavation companies focus on preserving historical artifacts while those in East Korujoare free to do whatever they want to extract as much wealth as possible. At the time of our story, the hurricane belt isn't expected to interfere with Korujo for another 100 years.