After the recent Great East Japan Earthquake of March 11, 2011, the importance of social capital has been heavily stressed. While there is a growing collection of literature on the role of social capital after disasters, other studies have mostly used qualitative analysis or quantitative methods using cross-sectional data from one point in time. This paper studied Time-Series-Cross-Section (TSCS) data from all 47 Japanese prefectures spanning about 30 years from 1981 to 2012. There are very few studies useing TSCS because available data is scarce. This paper employs proxies for social capital. The study found quantitatively that social capital plays important roles in the process of recovery, encouraging people to return to their homes and to stay. What happened to Tohoku as a result of the earthquake, tsunami, and nuclear power accident was the destruction of social capital on a huge scale. The population is still decreasing in the area. Social capital should be at the core of future planning to rebuild Tohoku. (C) 2015 Elsevier Ltd. All rights reserved.