Our goal is to test rival social scientific hypotheses with historical and archaeological data. Therefore, the Databank is systematically compiled with information about polities from around the globe.
In order to make this data collection manageable given our limited time and resources, we take a representative sample of polities from around the globe and throughout human history (specifically, the late Neolithic to the early modern period, roughly 4,000 BCE to 1,900 CE). This is our World Sample 30.
World Sample 30 Map
The World Sample-30 was designed with two goals in mind: (1) to include as much variation amongst sampled societies as possible, focussing along the dimension of social complexity , and (2) to ensure that representation of different parts of the world was maximized.
We selected 30 areas across the globe for our initial worldwide sample, stratified by world region and history of social complexity. We divided the world into ten major regions and then selected three natural geographic areas (NGAs) within each region: one NGA was selected in each world region that developed complex state-level societies very early; another NGA which selected complex societies very late (relative to other areas in that world region), ideally one free of centralized polities (chiefdoms and states) until the colonial period; and a third NGA that was intermediate in social complexity.
World Sample 30 NGAs
||Late appearance of complex polities
||Intermediate appearance of complex polities
||Early appearance of complex polities
||11-Niger Inland Delta
||3-Lena River Valley
||4-Yemeni Coastal Plain
||7-Southern China Hills
||27-Middle Yellow River Valley
||28-Valley of Oaxaca
||30-Big Island Hawaii