For agricultural populations, you need water, sunlight, nitrogen in the soil—and a way to get the crops out into the world or at least the local regional market. For industrial populations, you used to need raw materials transport in and finished goods transport out plus a community of engineering practice. For commerce, transport rules—shifting now to "a nice place to live". Best thing I have seen on the whole shebang is: J. Vernon Henderson, Adam Storeygard, Tim L. Squires, and David N. Weil: The Global Spatial Distribution of Economic Activity: Nature, History, and the Role of Trade <ttp://www.nber.org/papers/w22145>
