We present a theory of spatial development. A continuum of locations in a geographic area choose each period how much to innovate (if at all) in manufacturing and services. Locations can trade subject to transport costs and technology diffuses spatially across locations. The result is an...

"State per capita incomes became more disperse during the contraction phase of the Great Depression, and less disperse during the recovery phase. We investigate the effects of geography, industry structure, bank failures and fiscal policies on state income growth during each phase. We find that...