Urban Reconstruction and Population Redistribution: Evidence from Tokyo after the Great Kanto Earthquake

This study examines the impact of the 1923 Great Kanto Earthquake on population distribution within Tokyo City. The earthquake triggered massive fires that devastated nearly half of the city, including much of its urban core. To investigate its consequences, I digitized systematic census statistics and conducted regression analyses using variation in fire damage across areas. The results show that land readjustment implemented as part of the reconstruction project reduced residential land area within the burned area, leading to higher unit rents. Although the total residential floor area eventually recovered through the construction of multi-story dwellings, the population of the burned area remained below its pre-earthquake level throughout the period examined. In addition, the zoning system established before the earthquake had little effect on population redistribution. These findings suggest that post-disaster population distribution was shaped primarily by market-based price adjustments rather than institutional regulations. The analysis further shows that rising rents reduced the number of kinship households while increasing incentives for workers to rent rooms as lodgers. The rent burden borne by lodgers, relative to that borne by landlords, was lower in the burned area, making housing sharing an effective response. Overall, the post-disaster population decline in the burned area reflected the net effect of two opposing forces: population loss driven by rising rents and population retention through increased housing sharing among worker households seeking to mitigate those rent increases.